FIELD OF THE INVENTION

[0001] The present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates. Specifically, the present invention relates to a novel catalytic process for the synthesis of Fondaparinux pentasaccharide and its intermediates. The present invention further relates to a silver assisted gold catalysis for glycosylation reactions in the synthesis of Fondaparinux pentasaccharide and its intermediates.

BACKGROUND OF THE INVENTION

[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[0003] Sulfated linear polysaccharides consisting of alternating di saccharide units of a- 1,4-linked glucosamine and either glucuronic acid or iduronic acid such as heparin (H) and heparin sulfate (HS) are present on the surface of most animal cells, membranes and extracellular matrices. They play pivotal role in diverse biological pathways including tumor metastasis, cell growth, cell adhesion, wound healing, inflammation, diseases of central nervous system etc. Both H and HS are heavily O- and N-sulfated, they belong to glycosaminoglycan polysaccharides and are extracted and isolated from natural animal sources (porcine intestine or bovine lung or some-times from turkeys, mice, camel, whales, lobsters, etc.). H and HS are routinely used as anti -coagulant drugs during major surgeries such as cardiopulmonary bypass, knee replacement, hip replacement in order to prevent occurrence of venous thrombosis.

[0004] Porcine or bovine derived Heparin has been used in clinics for many decades as an anti-coagulant drug due to its strong affinity binding with anti-thrombin III thereby preventing the venous thrombosis. Unfractionated heparin (UFH) (MWavg -15000, -45 monosaccharide chains) and low molecular weight heparin (LMWH) (MWavg -6000) are marketed for a longtime. Several LMWHs are marketed under different trade names such as Enoxaparin, Nadroparin, Reviparin, Dalteparin, Tinzaparin, Certoparin, Danaparoid depending on the type of depolymeri-zation. For example, Enoxaparin is isolated from UFH after P-eliminative cleavage employ-ing alkali through peeling off reaction whereas Nadroparin is obtained by deaminative cleavage employing nitrous acid. Mechanistic investigations revealed that the H binds to antithrombin with high affinity, brings in a conformational change thereby converting it to a rapid (lOOOx) in-hibitor of thrombin (Flla). Apart from thrombin, antithrombin interacts with coagulation factor Xa (FXa). LMWHs derived by chemical and/or enzymatic depolymerization procedures from UFH vary in both their relative abilities to enhance the inhibition of FXa and Flla (anti-FIIa) and in their physicochemical properties. It has been noticed that specific FXa inhibitory activity increases as the mean molecular weight decreases. For example, UFH (MWavg -15000) has Anti-FXa/ Anti-FIIa activity ratio of 1.0 whereas the same ratio for Enoxaparin (MWavg -4200) is 3.9 and Bemiparin (MWavg -3600) was 8.0.12 However, chemically and enzymatically extracted H and HS from animal sources suffer from microheterogeneity, presence of viral or prion contaminants; and hence, strongly influence their purity and quality from batch to batch. The problem manifested into a pinnacle due to the worldwide distribution of contaminated animal-sourced heparin about a decade ago.

[0005] Much before, in 1980s, a unique pentasaccharide domain of heparin was found to be clinically effective as specific FXa inhibitor. This important discovery paved way to the chemically synthesized pentasaccharide that later led to the launch of the first synthetic anticoagulant antithrombotic Fondaparinux (Arixtra®) in 2004.

[0006] Fondaparinux is a synthetic pentasaccharide based on the antithrombin-binding domain of Heparin sulfate and contains glucosamine, glucuronic acid and iduronic acid in its sequence. Fondaparinux (MW = 1725) has well controlled pharmacokinetic and pharmacodynamics properties, is free from any viral or prion impurities, and importantly, is a specific FXa inhibitor. Clinically approved anti-coagulant Fondaparinux is safe since it has zero contamination problems often associated with animal based heparins. Extensive structure-property relationship studies proved that essential sulfate and carboxylic acid groups shall be located at opposite sides of the pentasaccharide. Despite its predictable anticoagulant dose and long half-life, Fondaparinuxis very expensive compared to H and HS derived from animals as its synthesis demands a long and tedious procedures diminishing the overall efficiency. Indeed, synthesis of Fondaparinux pentasaccharide and other heparin oligosaccharides is a herculean task due to intricacies involved in the installation and unblocking of multiple orthogonal protecting groups.

[0007] Since the first heroic synthesis of the pentasaccharide by Petitou in 1987, several synthetic strategies have been reported for the heparin fragments involving stepwise glycosylation invoking many protecting groups and glycosylation protocols. Given the complexity of Fondaparinux, very few total syntheses are reported to date and they mainly focused on the following aspects in order to improve the overall yield: (i) optimizing chemistry of individual monosaccharides (ii) identification of right pairs of orthogonal protecting groups and (iii) stereoselective glycosylation chemistry. On the other hand, HS polymerase, sulfotransferases and epimerases were employed for the enzymatic synthesis of the Fondaparinux.

[0008] In spite of a variety of synthetic procedures, access to differentially substituted derivatives is very significant for structure-property relationships of the Fondaparinux. Reported syntheses of the Fondaparinux pentasaccharide till date have modeled their convergent or linear or multiple one-pot strategies either by 3+2 or 3+1+1 combination of modular saccharide building blocks.

[0009] Thus there is an urgent need to develop a rapid and facile synthetic strategy for Fondaparinux that also enables creation of diverse molecular entities that differ in sulfation pattern. Need is also felt for novel process for the synthesis of Fondaparinux, which can overcome deficiencies associated with the known arts.

OBJECTS OF THE INVENTION

[0010] An object of the present invention is to provide a novel process for the synthesis of Fondaparinux, which can overcome deficiencies associated with the known arts.

[0011] Another object of the present invention is to provide a facile process for the synthesis of Fondaparinux that enables creation of diverse molecular entities differing in sulfation pattern.

[0012] Another object of the present invention is to provide a process for the synthesis of Fondaparinux that is scalable. [0013] Another object of the present invention is to provide a process for the synthesis of Fondaparinux that provides a scalable route for the synthesis of unnatural and expensive intermediate, Iduronic acid.

[0014] Yet another object of the present invention is to provide a process for the synthesis of Fondaparinux wherein all glycosidations reactions are carried out in catalytic fashion.

[0015] Still another object of the present invention is to provide a process for the synthesis of Fondaparinux that has minimal number of steps and facile purifications.

[0016] Yet another object of the present invention is to provide a process for the synthesis of Fondaparinux with excellent process efficiency.

[0017] The other objects and preferred embodiments and advantages of the present invention will become more apparent from the following description of the present invention when read in conjunction with the accompanying examples and figures, which are not intended to limit scope of the present invention in any manner.

SUMMARY OF THE INVENTION

[0018] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in Detailed Description section. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0019] The present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates. Specifically, the present invention relates to a novel catalytic process for the synthesis of Fondaparinux pentasaccharide and its intermediates.

[0020] The present invention further relates to a silver assisted gold catalyzed glycosylations for the synthesis of Fondaparinux pentasaccharide and its intermediates.

[0021] In one aspect, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all glycosidation steps are carried out in a catalytic fashion using silver assisted gold catalysis utilizing alkynylcyclohexyl carbonate donor chemistry.

[0022] In another aspect, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all glycosidation steps for linking monosachharide building blocks are carried out using silver assisted gold catalysis using Au-phosphite in the presence of AgOTf.

[0023] In another aspect, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalysed glycosidations are carried out for assembling the pentasaccharide in a highly convergent

[3+2] or [3+1+1] manner.

[0024] In another aspect, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalysed glycosidations are carried out for assembling the pentasaccharide by coupling trisaccharide fragment either with a disaccharide via 3+2 glycosylation or coupling trisaccharide with iduronate monosaccharide followed by coupling another monomer monosaccharide via 3+1+1 glycosylation.

[0025] In yet another aspect, the present invention relates to the process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the process comprises the steps of: a) Reacting trisaccharide DEF3 with either 3+2 glycosylation using disaccharide GH2 or by reacting trisaccharide DEF3 via 3+1+1 elongation by coupling iduronate GIO and azido-derivative H3, resulting in the formation of regioselectively protected pentasaccharide; and or

b) Deprotecting the regioselectively protected pentasaccharide, converting the azide to amine followed by regioselective sulfation, resulting in Fondaparinux.

[0026] In another aspect, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all the monosaccharide units are synthesized avoiding harsh reaction conditions or reagents.

[0027] Other aspects of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be leamt by the practice of the invention.

DETAILED DESCRIPTION

[0028] The following is a detailed description of embodiments of the disclosure. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.

[0029] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply. [0030] Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0031] In some embodiments, the numbers expressing quantities of ingredients, properties such as concentration, reaction conditions, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.”Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0032] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[0033] Unless the context requires otherwise, throughout the specification which follow, the word “comprise” and variations thereof, such as, “comprises” and “comprising” are to be construed in an open, inclusive sense that is as “including, but not limited to.”

[0034] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[0035] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

[0036] The description that follows, and the embodiments described therein, is provided by way of illustration of an example, or examples, of particular embodiments of the principles and aspects of the present disclosure. These examples are provided for the purposes of explanation, and not of limitation, of those principles and of the disclosure.

[0037] It should also be appreciated that the present disclosure can be implemented in numerous ways, including as a system, a method or a device. In this specification, these implementations, or any other form that the invention may take, may be referred to as processes. In general, the order of the steps of the disclosed processes may be altered within the scope of the invention.

[0038] The headings and abstract of the invention provided herein are for convenience only and do not interpret the scope or meaning of the embodiments.

[0039] The following discussion provides many example embodiments of the inventive subject matter. Although each embodiment represents a single combination of inventive elements, the inventive subject matter is considered to include all possible combinations of the disclosed elements. Thus if one embodiment comprises elements A, B, and C, and a second embodiment comprises elements B and D, then the inventive subject matter is also considered to include other remaining combinations of A, B, C, or D, even if not explicitly disclosed.

[0040] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.. [0041] The present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates. Specifically, the present invention relates to a novel catalytic process for the synthesis of Fondaparinux pentasaccharide and its intermediates.

[0042] The present invention further relates to a silver assisted gold catalyzed glycosylations for the synthesis of Fondaparinux pentasaccharide and its intermediates.

[0043] In one embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all glycosidation steps are carried out in a catalytic fashion using silver assisted gold catalysis utilizing alkynylcyclohexyl carbonate donor chemistry.

[0044] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all glycosidation steps for linking sachharide building blocks are carried out using silver assisted gold catalysis using Au-phosphite in the presence of AgOT futilizing alkynylcyclohexyl carbonate donor chemistry.

[0045] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalysed glycosidations are carried out for assembling the pentasaccharide in a highly convergent [3+2] or [3+1+1] manner.

[0046] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalysed glycosidations are carried out for assembling the pentasaccharide by coupling trisaccharide fragment either with a disaccharide via 3+2 glycosylation or coupling trisaccharide with iduronate monosaccharide followed by coupling another monomer monosaccharide via 3+1+1 glycosylation.

[0047] In yet another embodiment, the present invention relates to the process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the process comprises the steps of: a) Reacting trisaccharide DEF3 with either 3+2 glycosylation using disaccharide GH2 or by reacting trisaccharide DEF3 via 3+1+1 elongation by coupling iduronate G10 and azido-derivative H3, resulting in the formation of regioselectively protected pentasaccharide; and b) Deprotecting the regioselectively protected pentasaccharide, converting the azide to amine followed by regioselective sulfation, resulting in Fondaparinux.

[0048] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all the monosaccharide units are synthesized avoiding harsh reaction conditions or reagents.

[0049] In yet another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein glycosylation reactions are carried out in stereoselective manner. [0050] In still another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalysed glycosylation are carried out in stereoselective manner resulting in 1,2-cis- selectivity in excellent yield.

[0051] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein silver assisted gold catalyzed glycosylation reactions afford 1,2-czs-selectivity in excellent yield thereby facilitating easy purification of the desired compounds. The 1,2-czs-selectivity reaction at room temperature avoids the use of cumbersome cryogenic reaction conditions. An azide at the C-2 position strongly influences the stereochemical outcome of glycosidation in favor of desired 1,2-cis or a-glucoside.

[0052] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the trisaccharides DEF3 can be synthesized by stepwise glycosylation using alkynylglycosyl carbonates and silver assisted gold catalysed glycosidations.

[0053] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the trisaccharides DEF3 can be synthesized by coupling the fragments E10, F8 and D4, comprising the steps of: a) Coupling compound E10 with compound F8 using silver assisted gold catalysed glycosidation using Au-phosphite in the presence of AgOTf, resulting in the formation of compound EFl; b) Deprotecting the TBS group from EFl to obtain compound EF2; c) Coupling compound EF2 with compound D4 using silver assisted gold catalysed glycosidation using Au-phosphite in the presence of AgOTf, resulting in compound DEFI; d) Deprotecting the allyl group from DEFI resulting in compound DEF2; and e) Converting the secondary hydroxyl group of DEF2 into carbonate moiety resulting in tri saccharide compound DEF3.

[0054] According to embodiment of the present invention, the synthesis of trisaccharide

DEF3 is shown in detail in Scheme 1.

[0055] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein all the monosaccharide units can be synthesized starting from D-Glucose or D-Glucosamine. [0056] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein iduronic acid monosaccharide compound G13 is synthesized starting from D-Glucose by following the synthetic route as depicted in Scheme 2.

[0057] The intermediates Gl, G2, G3, G4, G8 and G9 can also be synthesized as per the literature procedure reported by Lohman, et al., in./. Org. Chem. 2003, 68, 7559-7561.

[0058] In still another embodiment, the present invention relates to a novel scalable route for the synthesis of unnatural and expensive iduronic acid compound.

[0059] According to the embodiments of the present invention, an alternate and novel synthetic route for the synthesis of compound G10 is reported.

[0060] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the compound G10 can be prepared from aldehyde G4, comprising the steps of: a) Adding thiophenylmagnesium bromide to aldehyde G4 resulting in ztfo-compound G5; b) Acetylation of compound G5 resulting in compound G6; c) Oxidation of thiophene moiety of compound G6, followed by esterification resulting in iduronate compoundG7; d) Deacetylation of compound G7 resulting in compound G8; e) Conversion of furanose of iduronate G8 under acidic conditions to pyranose compound G9; and f) Conversion of compound G9 to isopropylidene derivative GIO.

[0061] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the compound G13 is prepared from compound G10, comprising the steps of: a) Protecting the hydroxyl group of compound G10 with silyl protecting group resulting in compound Gil; b) Cleaving the isopropylidene group of compound Gil resulting in compound G12; and c) Coupling compound G12 with l-ethylnylcyclohexyl-(4-nitrophenyl) carbonate resulting in compound G13.

[0062] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein monosaccharide unit F8 is synthesized starting from Glucosamine, comprising the steps of: a) Protecting amine functionality of glucosamine with Troc protecting group resulting in compound Fl; b) Selective allyl protection of compound Fl resulting in compound F2; c) Reacting compound F2 with benzylidene-dimethyl acetal resulting in compound F3; d) Unmasking the Troc protecting group to obtain compound F4; e) Converting the amine of compound F4 to azide in compound F5; f) Protecting the lone hydroxyl group resulting in compound F6; g) Hydrolysing the benzylideneacetal of compound F6 to obtain compound F7; and h) Regioselective protection of C6-hydroxyl group of F7 to obtain compound F8.

[0063] The synthetic route for the synthesis of compound F8 is described in Scheme 3.

TrocCI (1.5 eq) AcCI (2.5 eq), AIIOH NaHCO ₃ (2.0 eq) 80 °C, 16h, 94% H ₂ O, RT, 16h, 85%

PhCH(OMe) ₂ (1.5 eq)

CSA (0.2 eq), DMF ph^srvo Zn dust (18 eq) ACOH:CH ₃ OH:CH ₂ CI ₂ Ph^STVq RT, 4h, 74% TrocHN _OA || RT, 1 h, 77% H ₂ N QAII

F3 F4

Azidosulfonylimidazole (1.4 eq) NaH (1.1 eq) K ₂ CO ₃ (2.4 eq), MeOH-THF (4:1) PMB-CI (1.2 eq) CUSO ₄ .5H ₂ O (cat), RT, 2h, 82% RT, 3h, 81%

PTSA (0.3 eq) Bz ₂ O (1.2 eq), Et ₃ N MeOH-CH ₂ CI ₂ (9.0 eq), RT, 12h RT, 1 h 74% 2 steps

[0064] The intermediate Fl can also be synthesized as per the literature procedure reported by Hou et al. in Eur. J. Med. Chem. 2017, 132, 1-10 and by Craftet al. in

Carbohydrate Res . 2017, 440-441, 43-50. [0065] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein monosaccharide unitH3 is synthesized starting from Glucosamine, using the advanced intermediate F5 synthesized during the synthesis of F8, following the synthetic route as described in Scheme

4

[0066] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein monosaccharide unit D4 is synthesized starting from Glucosamine, using the advanced intermediate H2, synthesized during the synthesis of H3, wherein the compound D4 is prepared from compound H2, comprising the steps of: a) Regioselective silyl protection of compound H2 resulting in compound DI; b) Benzyl protection of lone hydroxyl group of compound DI resulting in compound D2; c) Deprotecting the allyl group of compound D2 to obtain compound D3; and d) Coupling compound D3 with l-ethylnylcyclohexyl-(4-nitrophenyl) carbonate resulting in compound D4.

[0067] The synthetic route for the synthesis of compound D4 is described in Scheme 5.

HO'A TBDPSCI (1.2 eq), Et ₃ N TBDPSO^. > NaH (1.1 eq)

(5.0 eq), DMAP (0.5 eq) BnBr (1.2 eq)

^BnO ~^Tl ^R T ^16h ’ ⁷⁸ % ² BnO-^ ^I RT, 3h, 93%

^N 3OAII - ^ste P ^s ► ^N 3OAII

H2

PdCI ₂ (0.15 eq) Carbonate (1.2 eq) MeOH-CH ₂ CI ₂ DMAP (1.5 eq) RT, 4-8h, 85% DCM, RT, 3h, 92%

[0068] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the compound E10 is prepared from compound G2 comprising the steps of: a) Hydrolysis of isopropylidene group of benzyl protected diacetoneglucofuranoseGl resulting in compound El; b) Allyl protection of compound El under acidic conditions resulting in compound E2; c) Locking the C4 and C6 of compound E2 as benzylidene to obtain compound E3; d) Protecting the C2 hydroxyl of compound E3 as benzyl group to obtain compound E4; e) Hydrolysing the benzylidene group of compound E4 resulting in compound E5; f) Oxidation of primary hydroxyl group of compound E5 resulting in compound E6 which was then esterified to obtain compound E7; g) Silyl protection of compound E7 to obtain compound E8 followed by deallylation resulting in compound E9; and h) Coupling compound E9 with l-ethylnylcyclohexyl-(4-nitrophenyl) carbonate resulting in compound E10.

[0069] The synthetic route for the synthesis of compound ElOis depicted in Scheme 6.

[0070] The intermediate El can also be synthesized as per the literature procedure reported by Prentice et al. in J. Amer. Chem. Soc. 1956, 78, 4439-4440; Orgueira et al. in Chem. Eur. J. 2003, 9, 140-169 and by Zou et al. in Tetrahedron 2018, 74, 2376-2382. The intermediate E3 can also be synthesized as per the literature procedure reported by Patricia, et al. in Carbohydrate Research 1976, 49, 325-333.

[0071] In another aspect, the present invention provides shared use of functionalized building blocks for the synthesis of Fondaparinux pentasaccharide and its intermediates.

[0072] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the disaccharide compound GH2, required for coupling with the trisaccharide, is prepared by the process comprising the steps of : a) coupling compound G13 with compound H3, using silver assisted gold catalysed glycosidation using Au-phosphite in the presence of AgOTf, resulting in the formation of compound GH1; and b) deprotecting the TBS group from GH1 resulting in the formation of compound GH2.

[0073] According to embodiments of the present invention, synthesis of the disaccharide GH2 is depicted in Scheme 7.

[0074] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the pentasaccharide

DEFGH1 is prepared via 3+2 glycosidation, by coupling the trisaccharide DEF3 with the disaccharide GH2 using silver assisted gold catalysed glycosidation using Au-phosphite in the presence of AgOTf. The route of synthesis is described in Scheme 8.

[0075] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the pentasaccharide DEFGH2 is prepared via 3+1+1 glycosidation, by the process comprising the steps of : a) Coupling the trisaccharide DEF3 with monosaccharide G10 using silver assisted gold catalysed glycosidation using Au-phosphite in the presence of AgOTf, resulting in the formation of tetrasaccharide compound DEFG1; b) Deprotecting the acetonide and PMB protecting groups of compound DEFG1 to obtain compound DEFG2; c) Conversion of the compound DEFG2 to DEFG3 by reaction with carbonate 36; and d) Coupling compound H3 with DEFG3 to obtain the pentasaccharide DEFGH2.

[0076] According to the embodiments of the present invention, the route of synthesis of pentasaccharide DEFGH2 is prepared via 3+1+1 glycosidation is described in Scheme 9. [0077] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and its intermediates, wherein the pentasaccharide DEFGH1 is converted to a regioselectively protected pentasaccharide DEFGH5 by deprotecting the silyl and PMB protecting groups.

[0078] According to the embodiments of the present invention, the silyl and PMB protecting groups of pentasaccharide DEFGH1 can be removed in any sequence, either removing silyl group followed by the removal of PMB group or by first removing PMB group followed by deprotection of silyl group, resulting in pentasaccharide DEFGH5. The route has been described in Scheme 10.

[0079] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and novel intermediates, wherein certain steps in the synthesis may not require purification of the product obtained, but can be used as such in the next step. The products obtained at each step may or may not be always purified before proceeding further in the next step.

[0080] In yet another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and novel intermediates, wherein the synthetic route is useful for the synthesis of other glycosamino-glycans selected from but not limited to Hyaluronic acid, Keratan Sulfate, Chondroitin sulfate, Idraparinux, Idrabiotaparinux and the like.

[0081] In another embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and novel intermediates, wherein the regioselectively protected pentasachharide, DEFGH2 or DEFGH1 or DEFGH3 or DEFGH4 or DEFGH5 can be deprotected by using standard deprotection conditions, well known to a person skilled in the art. The different protecting groups like benzyl, benzoyl, acetate, allyl and ester can be deprotecting using synthetic methods as described in Greene’s Protective Groups In Organic Synthesis; 4 ^th Edition, Wiley Science; Chem. Sci. 2018, DOI: 10.1039/C8SC01743Cand in Angew. Chem. Int. Ed. 2014, 53, 9876 -9879. The azide group on the pentasaccharide are then converted to the required amine functionality using standard reduction conditions known to person skilled in the art, followed by introduction of regioselective O-sulphateand N-sulphate at desired positions through chemical sulphation, to obtain Fondaparinux. [0082] In a preferred embodiment, the present invention relates to a process for the synthesis of Fondaparinux pentasaccharide and novel intermediates selected from the group consisting of but not limited to: [0083] While the foregoing describes various embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof. The scope of the invention is determined by the claims that follow. The invention is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

[0084] The present invention is further explained in the form of following examples. However, it is to be understood that the following examples are merely illustrative and are not to be taken as limitations upon the scope of the invention.

[0085] All the starting materials used are commercially available. Unless otherwise noted, materials were obtained from commercial suppliers and were used without further purification.1-Ethynyl cyclohexanol, p-nitrophenyl chloroformate and all metal salts were purchased from Sigma-Aldrich. Unless otherwise reported all reactions were performed under Nitrogen atmosphere. Gold phosphite was purchased from Proactive Molecular Research, 13709 Progress Blvd. Suite S-166C, Mailbox 34 | Alachua, Florida 32615, USA. Removal of solvent in vacuo refers to distillation using a rotary evaporator attached to an efficient vacuum pump. Products obtained as solids or syrups were dried under high vacuum. Analytical thin-layer chromatography was performed on pre-coated silica plates (F254, 0.25 mm thickness); compounds were visualized by UV light or by staining with anisaldehyde spray. IR spectra were recorded on a FT-IR spectrometer. NMR spectra were recorded either on a 400 or a 500 MHz with CDC1 ₃ as the solvent and TMS as the internal standard. High resolution mass spectroscopy (HRMS) was performed using an ESI-TOF mass analyser. Low resolution mass spectroscopy (LRMS) was performed on UPLC-MS with SWADESI- TLC interface.

[0086] Example 1: Preparation of Compound G1

[0087] To a solution of D-glucose (40 g, 222 mmol) and 2,2-dimethoxy propane (2.5 eq) in dry acetone (600 mL) was added 0.5 equivalent of anhydrous CuSO4. After vigorously stirring for 30 min, 2.5 equivalent of concentrated H2SO4 was added dropwise under argon atmosphere and the reaction mixture was stirred at 25 °C for 24 h. After completion, the reaction was quenched by the addition of saturated aq.NaHCO3 solution, acetone was removed at reduced pressure in vacuo and the product was extracted with CH2C12. The organic layer was dried over anhydrous Na2SO4 and concentrated in vacuo. The crude product was precipitated by the addition of CH2C12 and hexane to afford 1,2:5,6-Di-O- isopropylidene-a-D-glucofuranoseGl (37.6 g, 65%) as a fluffy white solid, mp 105.2 °C; [a]25D (CHC13, cl.0): -11.8°; IR (cm-1, CHC13) : 3429, 2987, 2945, 1377, 1220, 1069, 1025, 851, 786, 754; 1H NMR (400.31 MHz, CDC13): 8 5.93 (d, J= 3.4 Hz, 1H), 4.52 (d, J= 3.5 Hz, 1H), 4.35 - 4.30 (m, 2H), 4.16 (dd, J = 8.5, 6.3 Hz, 1H), 4.05 (dd, J= 7.7, 2.5 Hz, 1H), 3.98 (dd, J= 8.6, 5.4 Hz, 1H), 2.69 - 2.63 (m, 1H), 1.49 (s, 3H), 1.43 (s, 3H), 1.35 (s, 3H), 1.31 (s, 3H);13C NMR (100.67 MHz, CDC13): 8 111.8, 109.7, 105.3, 85.1, 81.1, 75.2, 73.4, 67.6, 26.8, 26.8, 26.2, 25.1; HRMS (ESI-MS): m/z calcd for C12H20O6 [M+H]+: 261.1338, Found: 261.1336.

[0088] Example 2: Preparation of Compound G2

[0089] To a solution of l,2:5,6-Di-O-isopropylidene-a- D-glucofuranose G1 (60g, 231 mmol) in anhydrous THF (300 mL), NaH (60% in mineral oil, 1.2 eq) was added in portions under argon atmosphere. After evolution of the hydrogen ceased, benzyl bromide (1.1 eq) was added dropwise, followed by the addition of catalytic tetrabutyl ammonium iodide (0.05 eq) and the mixture was stirred at 25 °C for 3 h. After completion, the reaction mixture was quenched by the addition of ice-cold water (500 mL) and extracted with EtOAc (3 x 300 mL). The combined organic phases were washed with brine, dried over anhydrous Na2SO4 and concentrated in vacuo. The crude residue was purified by silica gel column chromatography using 8% ethyl acetate in //-hexane as a mobile phase to afford compound G2 (74g, 92%) as a thick syrup. [a]25D (CHC13, cl.0): -30.0°; IR (cm-1, CHC13): 2986, 2936, 1377, 1255, 1076, 1023, 851, 748;1H NMR (400.31 MHz, CDC13): 8 7.37 - 7.27 (m, 5H), 5.90 (d, J= 3.7 Hz, 1H), 4.71 - 4.62 (m, 2H), 4.59 (d, J= 3.7 Hz, 1H), 4.37 (dt, J= 7.7, 6.0 Hz, 1H), 4.15 (dd, J= 7.8, 3.1 Hz, 1H), 4.12 (dd, J= 8.6, 6.2 Hz, 1H), 4.04 - 3.99 (m, 2H), 1.50 (s, 3H), 1.43 (s, 3H), 1.38 (s, 3H), 1.31 (s, 3H);13C NMR (100.67 MHz, CDC13): 8 137.7, 128.4, 128.4, 127.8, 127.7, 127.7, 111.8, 109.0, 105.3, 82.7, 81.7, 81.3, 72.5, 72.4, 67.4, 26.9, 26.8, 26.3, 25.5; HRMS (ESI-MS): m/z calcd for C19H26O6 [M+Na]+: 373.1627, Found: 373.1638. [0090] Example 3: Preparation of Compound G3

[0091] Diacetonide compound G2 (38 g, 108.4 mmol) was dissolved in 380 mL of the 66.6% aqueous acetic acid and the mixture was stirred at 50 °C for 8 h. After removal of the solvent under reduced pressure, the remaining residue was co-evaporated twice with water and twice with toluene and the crude residue was purified by silica gel column chromatography to afford 30 g (89%) of the diol compound G3 as a white solid. [a]25D (CHC13, cl.0): - 55.8°; IR (cm-1, CHC13): 3387, 2932, 1639, 1457, 1253, 1216, 1077, 1019, 894, 858, 742, 7OO;1H NMR (399.78 MHz, CDC13): 8 7.38 - 7.27 (m, 5H), 5.91 (d, J= 3.8 Hz, 1H), 4.70 (d, J= 11.8 Hz, 1H), 4.60 (d, J= 3.8 Hz, 1H), 4.56 (d, J= 11.8 Hz, 1H), 4.14 - 4.08 (m, 2H), 4.02 (m, 1H), 3.79 (d, J= 9.3 Hz, 1H), 3.67 (dd, J= 11.5, 5.4 Hz, 1H), 2.94 (d, J = 5.6 Hz, 1H), 2.84 (s, 1H), 1.47 (s, 3H), 1.30 (s, 3H);13C NMR (100.53 MHz, CDC13): 8 137.3, 128.7, 128.7, 128.2, 127.9, 127.9, 111.9, 105.2, 82.2, 82.0, 80.0, 72.2, 69.2, 64.4, 26.8, 26.3; HRMS (ESI-MS): m/z calcd for C16H22O6 [M+Na]+: 333.1314, Found: 333.1320.

[0092] Example 4: Preparation of Compound G4

[0093] Compound G3 (29g, 93.4mmol) was dissolved in 870 mL of methanol and the mixture was cooled to 0°C. NaIO4 (1.2 eq) was dissolved in 290 mL of water, slowly added to the reaction mixture and stirred for 45 min. After completion, the reaction was filtered through a bed of Celite®, the filtrate was concentrated in vacuo and extracted with CH2C12 (3 x 500mL). The combined organic layers were washed with brine solution (500 mL), dried over anhydrous Na2SO4 and concentrated in vacuo. The crude was passed through a silica gel column to obtain the desired aldehyde compound G4 (26 g, quantitative). [a]25D (CHC13, cl.0): -45.2°; IR (cm-1, CHC13): 3485, 2988, 2938, 1737, 1456, 1380, 1260, 1078, 1021, 752; 1H NMR (399.78 MHz, CDC13): 8 9.67 (d, J= 1.5 Hz, 1H), 7.37 - 7.29 (m, 4H), 7.25 - 7.23 (m, 1H), 6.12 (d, J = 3.5 Hz, 1H), 4.65 (d, J = 3.5 Hz, 1H), 4.61 (d, J = 11.8 Hz, 1H), 4.57 (dd, J = 3.8, 1.5 Hz, 1H), 4.48 (d, J= 11.9 Hz, 1H), 4.34 (d, J = 3.8 Hz, 1H), 1.47 (s, 3H), 1.33 (s, 3H).; 13C NMR (100.53 MHz, CDC13):8 200.0, 136.7, 128.7, 128.7, 128.3 127.8, 127.8, 112.7, 106.3, 84.7, 83.8, 82.3, 72.4, 27.1, 26.4; HRMS (ESI-MS): m/z cal cd for C15H18O5 [M+H]+: 279.1232, Found: 279.1233.

[0094] Example 5: Preparation of Compound G5

[0095] Aldehyde compound G4 (10 mmol) was dissolved in 30 mL of the anhydrous Et2O or THF and added dropwise to the freshly prepared Grignard reagent (1.5 eq) at 0°C under argon atmosphere. Reaction mixture was allowed to stir at 25 °C for 3h. After completion, the reaction was quenched by the addition of excess amount of saturated aqueous ammonium chloride solution, water (150 mL) and extracted with EtOAc (3 x 100 mL). The combined organic phases were washed with brine solution (100 mL), dried over Na2SO4 and concentrated in vacuo. The crude residue was purified by silica gel column chromatography using 10-15% ethyl acetate in //-hexane as mobile phase to afford the compound G5 [89% (10: 1) when Et2O as a solvent whereas 82% (5: 1) when THF as a solvent]as Ido:Glc isomers. Reagent Preparation: To a freshly activated Mg-metal (1.5 eq) suspended in 30 mL of the anhydrous Et2O or THF in a two neck flask equipped with reflux condenser was added 2- thienyl bromide (1.5 eq) slowly under argon atmosphere and mixture was stirred at 45 °C for Ih). G5 (Ido isomer): thick syrup; [a]25D (CHC13, cl.0): -46.3°; IR (cm-1, CHC13): 3496, 3010, 2923, 1456, 1379, 122, 1215, 1075, 1018, 746, 703; IH NMR (399.78 MHz, CDC13): 8 7.38 - 7.25 (m, 6H), 7.01 (d, J= 3.4 Hz, IH), 6.95 (dd, J= 5.0, 3.5 Hz, IH), 6.02 (d, J= 3.8 Hz, IH), 5.35 (d, J= 7.6 Hz, IH), 4.63 (d, J= 3.8 Hz, IH), 4.58 (d, J= 11.5 Hz, IH), 4.41 - 4.35 (m, 2H), 3.80 (d, J = 3.3 Hz, IH), 2.99 (s, IH), 1.50 (s, 3H), 1.32 (s, 3H); 13C NMR (100.53 MHz, CDC13): 8 142.6, 137.1, 128.7, 128.7, 128.2, 127.7, 127.7, 126.7, 125.3, 125.2, 112.2, 105.4, 84.6, 82.3, 82.3, 72.0, 68.7, 27.0, 26.4; HRMS (ESI-MS): m/z calcd for C19H22O5S[M+Na]+: 385.1086, Found: 385.1086. G5 (Glc isomer): thick syrup; [a]25D (CHC13, c0.45): -61.4°; IR (cm-1, CHC13): 3489, 3010, 2929, 1498, 1379, 1261, 1217, 1077, 1025, 753, 703; IH NMR (400.31 MHz, CDC13): 8 7.39 - 7.30 (m, 5H), 7.26 (dd, J= 5.0, 1.2 Hz, IH), 7.02 (dt, J= 2.5, 1.0 Hz, IH), 6.98 (dd, J= 5.0, 3.5 Hz, IH), 6.03 (d, J = 3.8 Hz, IH), 5.31 (t, J= 6.4 Hz, IH), 4.68 (d, J= 11.4 Hz, IH), 4.64 (d, J= 3.8 Hz, IH), 4.52 (d, J = 11.4 Hz, IH), 4.38 (dd, J= 6.2, 3.3 Hz, IH), 4.16 (d, J= 3.3 Hz, IH), 3.38 (d, J = 7.1 Hz, IH), 1.49 (s, 3H), 1.32 (s, 3H); 13C NMR (100.67 MHz, CDC13): 8 145.4, 136.8, 128.9, 128.9, 128.5, 128.1, 128.1, 127.0, 125.0, 124.5, 112.0, 105.4, 83.1, 82.6, 81.9, 72.5, 69.0, 27.0, 26.4; HRMS (ESI-MS): m/z calcd for C19H22O5S[M+Na]+: 385.1086, Found: 385.1083.

[0096] Example 6: Preparation of compound G6

[0097] To a solution of 13.0 g (35.87mmol) of the compound G5 (Ido isomer) in anhydrous CH2C12 (65 mL) was added DMAP (1.2eq) under argon atmosphere, followed by dropwise addition of the acetic anhydride (1.5 eq). The reaction mixture was stirred at 25 °C for 1 h. After completion, the mixture was purified by silica gel column chromatography using 18% ethyl acetate in //-hexane as a mobile phase to obtain compound G6 (13.8 g, 95%) as a thick syrup. [a]25D (CHC13, cl.0): +20.8°; IR (cm-1, CHC13): 2988, 2933, 1742, 1453, 1375, 1226, 1076, 1018, 752, 705; 1H NMR (400.31 MHz, CDC13): 8 7.35 - 7.21 (m, 6H), 7.10 - 7.05 (m, 1H), 6.94 (dd, J= 5.1, 3.5 Hz, 1H), 6.40 (d, J = 9.3 Hz, 1H), 6.00 (d, J= 3.8 Hz, 1H), 4.62 (dd, J = 9.3, 3.3 Hz, 1H), 4.56 (d, J = 3.8 Hz, 1H), 4.43 (d, J = 11.5 Hz, 1H), 4.21 (d, J= 11.4 Hz, 1H), 3.67 (d, J= 3.3 Hz, 1H), 2.05 (s, 3H), 1.54 (s, 3H), 1.31 (s, 3H); 13C NMR (100.67 MHz, CDC13): 8 170.0, 139.1, 137.1, 128.5, 128.5, 128.0, 127.7, 127.7, 127.2, 126.7, 125.9, 112.0, 105.7, 82.2, 82.2, 81.8, 72.1, 69.7, 27.0, 26.4, 21.4; HRMS (ESIMS): m/z calcd for C21H24O6S[M+Na]+: 427.1191, Found: 427.1187.

[0098] Example 7: Preparation of Compound G7

[0099] To a solution of compound G6 (13.2 g, 32.63 mmol) in hexane-EtOAc (240 mL, 1 :3) was added a solution of NaIO4 (8 eq) in H2O (240 mL) at 25 °C and stirred for 10 min. Catalyst RuC13-3H2O (5mol%) was added and the mixture was stirred vigorously for 24 h. NaCl was added to saturate the aqueous layer, two phases were separated and the aqueous layer was extracted with EtOAc (2 x 100 mL). The combined organic phases were washed with brine solution (100 mL), dried over Na2SO4 and concentrated in vacuo. The crude product was dissolved in anhydrous DMF (100 mL) and added 1.5 equivalent of K2CO3. After stirring for 15 min, iodomethane (2 eq) was added under argon atmosphere and the mixture was stirred at 25 °C for 8 h in a dark place. After complete consumption, the reaction was quenched by adding excess of saturated solution of Na2SO3, brine (100 mL) and water (200 mL) and extracted by EtOAc (2 x 200 mL). The combined organic phases washed with brine, dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude was purified by column chromatography using 18% ethyl acetate in //-hexane as a mobile phase to obtain the desired compound G7(9.2 g, 74%) over two steps. Thick syrup; [a]25D (CHC13, cl.8): -3.4°; IR (cm-1, CHC13): 2956, 1747, 1446, 1376, 1216, 1076, 1024, 745, 700;H NMR (400.31 MHz, CDC13): 8 7.38 - 7.27 (m, 5H), 5.97 (d, J = 3.6 Hz, 1H), 5.52 (d, J= 7.1 Hz, 1H), 4.66 - 4.58 (m, 3H), 4.51 (d, J= 11.4 Hz, 1H), 4.16 (d, J= 3.8 Hz, 1H), 3.69 (s, 3H), 2.11 (s, 3H), 1.50 (s, 3H), 1.34 (s, 3H);13C NMR (100.67 MHz, CDC13): 8 170.0, 168.5, 137.2, 128.6, 128.6, 128.1, 127.9, 127.9, 112.6, 105.3, 83.0, 82.7, 78.8, 72.5, 70.8, 52.7, 27.2, 26.7, 20.9; HRMS (ESI-MS): m/z calcd for C19H24O8 [M+Na]+: 403.1369, Found: 403.1369.

[00100] Example 8: Preparation of Compound G8

[00101] To a solution of the compound G7 (9.18 g, 24.13 mmol) in anhydrous CH3OH (30 mL, 1 : 1), freshly prepared IM NaOMe in MeOH (0.3 eq) was added and the reaction mixture was stirred at 25 °C for 30 minute. After complete consumption of the starting material, Amberlite IR 120 (H+) (1.0 g per mol) was added to the reaction mixture to quench the NaOMe. After complete neutralization, the solid resin was filtered off and the filtrate was concentrated in vacuo xe. crude product was purified by silica gel column chromatography to obtain the compound G8 (7.7 g, 94%). Eluent for purification: 30% ethyl acetate in w-hexane; thick syrup; [a]25D (CHC13, cl.0): -39.8°; IR (cm-1, CHC13): 3448, 2988, 2954, 1740, 1451, 1378, 1255, 1214, 1075, 1025, 861, 743, 7O1;1H NMR (399.78 MHz, CDC13): 8 7.36 - 7.27 (m, 5H), 5.99 (d, J = 3.9 Hz, 1H), 4.70 (d, J = 11.6 Hz, 1H), 4.66 (d, J = 3.8 Hz, 1H), 4.54 - 4.48 (m, 3H), 4.17 (d, J = 3.4 Hz, 1H), 3.71 (s, 3H), 3.40 (d, 1H), 1.46 (s, 3H), 1.32 (s, 3H);13C NMR (100.53 MHz, CDC13): 8 172.0, 136.8, 128.6, 128.6, 128.2, 128.0, 128.0, 112.5, 105.2, 83.0, 83.0, 80.3, 72.4, 69.9, 52.7, 27.1, 26.7; HRMS (ESI-MS): m/z calcd for C17H22O7 [M+Na]+: 361.1263, Found: 361.1266.

[00102] Example 9: Preparation of Compound G9

[00103] Compound G8 (1.54 g, 4.55 mmol) was dissolved in 90% aqueous trifluoroacetic acid (10 mL) and stirred for 15 min at room temperature. The solvent was evaporated and the residue was co-evaporated twice with water and twice with toluene. Crude product G9 was carried to the next reaction.

[00104] Example 10: Preparation of compound G10

[00105] Compound G9 from above reaction was dissolved in anhydrous THF (6 mL) and added 2-methoxypropene (8.7 mL, 20 eq) under argon atmosphere. The reaction mixture was cooled to 0 °C and PTSA (0.1 eq) in THF (0.5 mL) was added dropwise with stirring. The mixture was allowed to warm to room temperature and stirred for 4 h. The reaction was quenched by the addition of Et3N, water (50 mL) was added and extracted with EtOAc (3 x 20 mL). The combined organic phases were washed with saturated aqueous NaHCO3 and brine solution, dried over anhydrous Na2SO4 and concentrated in vacuo. The crude residue was purified by column chromatography using 20% ethyl acetate in //-hexane as a mobile phase to obtain 850 mg (55%, over two steps) of the desired compound G10 as a thick syrup; [a]25D (CHC13, cl.0): -15.8°; IR (cm-1, CHC13): 3535, 2924, 2857, 1763, 1737, 1458, 1379, 1229, 1119, 1061, 846, 703; 1H NMR (400.31 MHz, CDC13): 8 7.40 - 7.30 (m, 5H), 5.36 (d, J = 1.9 Hz, 1H), 4.71 (d, J = 11.7 Hz, 1H), 4.64 (d, J = 11.7 Hz, 1H), 4.49 (s, 1H), 4.12 - 4.06 (m, 2H), 3.97 (q, J = 2.0 Hz, 1H), 3.81 (s, 3H), 3.12 (d, J = 11.3 Hz, 1H), 1.63 (s, 3H), 1.38 (s, 3H); 13C NMR [00106] Example 11: Preparation of Compound Gil

[00107] To a solution of alcohol G10 (280 mg, 0.828 mmol) in anhydrous CH2C12 (5 mL) was added 5.0 equivalent of 2,6-lutidine. TBDMSOTf (1.2 eq) was added dropwise at 0 °C under argon atmosphere and the resulting reaction mixture was stirred at 25 °C. After 15 min, ice-cold water (10 mL) was added and extracted with CH2C12 (2 x 10 mL). The combined organic phases were washed with brine, dried over anhydrous Na2SO4 and concentrated in vacuo, crude residue was purified by silica gel column chromatography using 10% ethyl acetate in w-hexane as a mobile phase to obtain 350 mg (93%) of the compound Gil as a thick syrup; [a]25D (CHC13, c0.8): -61.4°; IR (cm-1, CHC13): 2926, 2858, 1770, 1461, 1376, 1238, 1144, 1099, 1068, 835, 776; 1H NMR (400.31 MHz, CDC13): 6 7.40 - 7.30 (m, 5H), 5.32 (d, J = 2.5 Hz, 1H), 4.65 (q, J= 12.0 Hz, 2H), 4.38 (d, J= 1.3 Hz, 1H), 4.07 (dt, J= 2.5, 1.2 Hz, 1H), 3.95 (t, J= 2.7 Hz, 1H), 3.83 (t, 1H), 3.76 (s, 3H), 1.59 (s, 3H), 1.38 (s, 3H), 0.82 (s, 9H), -0.05 (s, 3H), -0.07 (s,3H); 13C NMR (100.67 MHz, CDC13): 8 169.8, 137.4, 128.8, 128.3, 128.0, 112.3, 96.9, 75.3, 75.1, 72.8, 72.6, 68.0, 52.2, 28.3, 26.6, 25.6, 18.0, -4.5, -5.3; HRMS (ESI-MS): m/z calcd for C23H36O7Si[M+Na]+: 475.2128, Found: 475.2130

[00108] Example 12: Preparation of Compound G12

OBn Dichloroacetic acid OBn MeO ₂ C "77110'^' (75% aqueous) MeO ₂ C "77110' 1 r i ⁰ RT, 2h, 81 % r r ° ^H TBDMSO O-^T / TBDMSO OH

G11 G12

[00109] To the compound Gil (310 mg, 684.9 pmol) in a 50 mL flask was added 75% aq. di chloroacetic acid (7 mL) at 0 °C and the solution was stirred at 0-25 °C for 1-2 h. After completion, the reaction was diluted with ice-cold water (30 mL), neutralized with NaHCO3 (4 g) and extracted with CH2C12 (3 x 15 mL). The combined organic phases were washed with saturated aqueous NaHCO3 and brine solution, dried over anhydrous Na2SO4 and concentrated in vacuo. The crude residue was further purified by silica gel column chromatography using 30% ethyl acetate in //-hexane as mobile phase to afford 230 mg (81%) of the compound G12 as a thick syrup; [a]25D (CHC13, c 0.7): -7.7°; IR (cm- 1, CHC13): 3504, 2956, 2925, 2858, 1740, 1461, 1373, 1214, 1140, 1082, 916, 839, 777;1H NMR (400.31 MHz, CDC13): 8 7.43 - 7.30 (m, 5H), 4.98 (d, J= 12.4 Hz, 1H), 4.68 (d, J = 12.1 Hz, 1H), 4.66 - 4.55 (m, 2H), 4.09 - 4.05 (m, 1H), 3.81 - 3.71 (m, 4H), 3.70 - 3.62 (m, 1H), 3.47 (d, J = 11.7 Hz, 1H), 0.83 (s, 9H), -0.03 (d, J = 2.7 Hz, 6H); 13C NMR (100.67 MHz, CDC13): 8 169.4, 137.2, 128.9, 128.9, 128.5, 128.1,

[00110] 128.1, 93.1, 75.4, 74.6, 72.6, 69.2, 68.5, 52.5, 25.6 (3C), 18.0, -4.8, -5.4; HRMS

(ESI-MS): m/z calcd for C20H32O7Si[M+Na]+: 435.1815, Found: 435.1818.

[00111] Example 13: Preparation of Compound G13

[00112] To a solution of G12 (155 mg, 375.71 pmol) in anhydrous CH2C12 (2 mL), DMAP (138 mg, 3.0 eq) and ethynyl cyclohexyl (4-nitrophenyl) carbonate (130 mg, 1.2 eq) were added and the reaction mixture was stirred at 25 °C for 3 h. After complete consumption of the starting hemiacetal, acetic anhydride (71 pL, 2.0 eq) was added and the stirring continued for another 2 h. The reaction mixture was concentrated in vacuo and purified by silica gel column chromatography using 15% ethyl acetate in //-hexane as mobile phase to obtain G13 (220 mg, 97%) of the desired carbonate donor as a thick syrup; [a]25D (CHC13, c0.8): -24.7°; IR (cm-1, CHC13): 3289, 2929, 2860, 1764, 1742, 1455, 1370, 1223, 1147, 1075, 1012, 915, 835, 755;1H NMR (399.78 MHz, CDC13): 8 7.37 - 7.30 (m, 5H), 5.91 (d, J = 1.8 Hz, 1H), 5.06 - 5.03 (m, 1H), 4.76 (d, J= 12.1 Hz, 1H), 4.60 (d, J= 7.0 Hz, 1H), 4.59 (d, J= 2.8 Hz, 1H), 3.94 (t, J= 2.3 Hz, 1H), 3.75 - 3.73 (m, 4H), 2.62 (s, 1H), 2.21 - 2.11 (m, 2H), 2.08 (s, 3H), 1.90 - 1.81 (m, 2H), 1.69 - 1.50 (m, 5H), 1.34 - 1.29 (m, 1H), 0.78 (s, 9H), -0.12 (s, 3H), -0.23 (s, 3H); 13C NMR (100.53 MHz, CDC13): 8 170.8, 168.4, 151.1, 137.0, 128.7, 128.7, 128.4, 128.3, 128.3, 93.1, 82.6, 78.6, 76.4, 75.4, 75.0, 72.6, 68.2, 66.3, 52.3, 36.9, 36.7, 25.6 (3C), 25.0, 22.6, 22.6, 21.2, 17.9, - 4.5, -5.7; HRMS (ESI-MS): m/z calcd for C31H44O10Si[M+Na]+: 627.2601, Found: 627.2605.

[00113] Example 14: Preparation of Compound Fl

[00114] To a solution of glucosamine hydrochloride (50 g, 231.88 mmol) in water (500 mL) was added NaHCO3 (38.96 g, 463.76 mmol). After stirring for 30 min TrocCl (46.34 mL, 347.82 mmol) was added drop-wise and the mixture was stirred at 25 °C. After 16 h, the reaction mixture was filtered through Whatman filter paper, residue was washed with water and CH2C12-hexane (1 :4), dried over a high vacuum to get 70 g (85%) of the compound Fl.

[00115] Example 15: Preparation of Compound F2

[00116] A solution of the Troc-GluN compound Fl (115 g, 324.34 mmol) in anhydrous allyl alcohol (1.1 L, 16.22 mol) was cooled to 0°C and acetyl chloride (57.86 mL, 810.86 mmol) was added dropwise under argon atmosphere. After stirring at 0 °C for 1 h, the reaction mixture was refluxed at 80 °C for 15 h, the reaction was quenched with Et3N and the volatile components were removed under reduced pressure. The product was precipitated by stirring crude compound in methanol-CH2C12-hexane (1 :2:4) solvent mixture. The residue was filtered through Whatman filter, washed with CH2C12- Hexane (1 :4) and dried over high vacuum; successfully afforded 100 g of the pure white solid. The filtrate was evaporated and purified by column chromatography to get overall 120 g (94%) of the compound F2. mp 121.3 °C; [a]25D (CHC13, c 1.0):+89.7°; IR (cm-1, CHC13): 3320, 2961, 2920, 1712, 1543, 1272, 1034, 755; 1H NMR (399.78 MHz, CD3OD): 8 5.99 - 5.88 (m, 1H), 5.33 (dq, J= 17.4, 1.6 Hz, 1H), 5.16 (dq, J= 10.5, 1.4 Hz, 1H), 4.88 (d, J= 2.3 Hz, 1H), 4.85 (s, 1H), 4.70 (d, J = 12.1 Hz, 1H), 4.21 (ddt, J = 13.2, 5.0, 1.4 Hz, 1H), 4.01 (ddt, J = 13.3, 6.0, 1.2 Hz, 1H), 3.82 (dd, J = 11.8, 2.2 Hz, 1H), 3.72 - 3.57 (m, 4H), 3.36 (dd, J = 9.7, 8.3 Hz, 1H); 13C NMR (100.53 MHz, CD3OD): 8 156.8, 135.4, 117.6, 97.8, 97.1, 75.5, 73.9, 72.7, 72.2, 69.1, 62.6, 57.3; HRMS (ESI-MS): m/z calcd for C12H18C13NO7 [M+Na]+: 416.0047, Found: 416.0046

[00117] Example 16: Preparation of Compound F3

HOA _Q PhCH(OMe) ₂ (1.5 eq) Ph^OTA _o

TrocHN Q _A || RT, 4h, 74% TrocHN J _AN

F2 F3

[00118] To a solution of the compound F2 (120 g, 304.09 mmol) and benzaldehyde dimethyl acetal (68.46 mL, 456.13 mmol) in anhydrous DMF (500 mL) was added camphorsulfonic acid (14.13 g, 60.82 mmol) portion-wise under argon atmosphere and the mixture stirred at 25 °C for 4 h. After completion, the reaction was quenched by dropwise addition of the ice-cold saturated aq NaHCO3 solution (500 mL), then 500 mL of water was added and extracted with EtOAc (3 x 300 mL). The organic layers were washed with brine (3 x 300 mL), dried over Na2SO4 and concentrated in vacuo. The product was precipitated by stirring crude residue in the combination of methanol -water (1 : 1) solvent mixture and after filtration, residue was washed with methanol-water (1 : 1) followed by CH2C12-Hexane (1 :4), dried under high vacuum to afford 98 g of the pure white. Further the filtrate was evaporated and purified by column chromatography to get an overall 108 g (74%) of the compound F3. mp 172.5 °C; [a]25D (CHC13, cl.0): +66.9°; IR (cm-1, CHC13): 3336, 2955, 2870, 1710, 1541, 1375, 1269, 1086, 754; 1H NMR (399.78 MHz, CDC13): 8 7.54 - 7.47 (m, 2H), 7.42 - 7.35 (m, 3H), 5.88 (ddt, J = 16.6, 10.8, 5.8 Hz, 1H), 5.52 (s, 1H), 5.39 (d, J = 9.2 Hz, 1H), 5.30 (d, J= 17.1 Hz, 1H), 5.23 (d, J= 10.3 Hz, 1H), 4.90 (d, J= 3.5 Hz, 1H), 4.83 (d, J= 12.1 Hz, 1H), 4.65 (d, J= 12.1 Hz, 1H), 4.25 (dd, J= 10.0, 4.6 Hz, 1H), 4.18 (dd, J= 12.8, 5.3 Hz, 1H), 4.02 - 3.89 (m, 2H), 3.88 - 3.79 (m, 2H), 3.72 (t, J = 10.2 Hz, 1H), 3.54 (t, J= 9.1 Hz, 1H), 3.11 (d, J = 3.3 Hz, 1H); 13C NMR (100.53 MHz, CDC13): 8 155.0, 137.1, 133.3,

129.4, 128.4, 128.4, 126.4, 126.4, 118.4, 102.0, 97.1, 95.5, 81.9, 74.8, 69.8, 68.8, 68.7, 62.7, 55.8; HRMS (ESI-MS): m/z calcd for C19H22C13NO7 [M+Na]+: 504.0360, Found: 504.0360 & 506.0321

[00119] Example 17: Preparation of Compound F4

[00120] To a solution of the compound F3 (98 g, 203.01 mmol) in 1 :2 CH2C12-MeOH (60 mL) was added 20 mL of glacial acetic acid. Zinc (239 g, 3.65 mol) was added portionwise at 0 °C and the mixture was stirred at 25 °C for 1 h, filtered through a bed of Celite®, the residue was washed with excess CH2C12 and filtrate was concentrated under reduced pressure. The resulting crude residue was treated with saturated aq NaHCO3 solution (300 mL) and extracted with CH2C12 (3 x 200 mL). The combined organic phases were washed with brine (200 mL), dried over Na2SO4 and concentrated in vacuo. The crude residue was passed through a small bed of silica gel using 4% methanol in CH2C12 as the mobile phase to afford 48 g (77%) of the compound F4 as a thick syrup; [a]25D (CHC13, cl.0): +108.3°; IR (cm-l,CHC13): 3275, 2917, 2865, 1604, 1571, 1457, 1376, 1082, 1016, 929, 754, 698; 1H NMR (400.31 MHz, CDC13): 8 7.52 - 7.45 (m, 2H), 7.40 - 7.32 (m, 3H), 5.91 (dddd, J = 16.5, 10.4, 6.1, 5.4 Hz, 1H), 5.52 (s, 1H), 5.30 (dq, J= 17.2, 1.6 Hz, 1H), 5.21 (dq, J = 10.4,

1.3 Hz, 1H), 4.83 (d, J= 3.6 Hz, 1H), 4.25 (dd, J= 10.1, 4.8 Hz, 1H), 4.20 (ddt, J= 12.8, 5.3,

1.4 Hz, 1H), 4.00 (ddt, J = 12.8, 6.1, 1.3 Hz, 1H), 3.84 (td, J= 9.9, 4.7 Hz, 1H), 3.73 (td, J = 10.3, 9.8, 5.4 Hz, 2H), 3.45 (t, J= 9.3 Hz, 1H), 2.80 (dd, J= 9.7, 3.6 Hz, 1H), 2.68 (s, 3H); 13C NMR (100.67 MHz, CDC13): 8 137.4, 133.8, 129.3, 128.4, 128.4, 126.4, 126.4, 117.8, 102.0, 99.3, 82.2, 71.7, 69.2, 68.8, 62.9, 56.6; HRMS (ESI-MS): m/z calcd for C16H21NO5 [M+H]+: 308.1498, Found: 308.1501.

[00121] Example 18: Preparation of Compound F5

[00122] To a solution of the compound F4 (50g, 162.68 mmol) in MeOH:THF (750 mL, 4: 1) was added K2CO3 (53.96 g, 390.44 mmol) and CuSO4»5H2O (406 mg, 1.63 mmol). Imidazole- 1 -sulfonyl azide hydrochloride (47.74 g, 227.76 mmol) was added portion-wise and the mixture stirred at 25 °C for 2 h. The mixture was concentrated, diluted with ice-cold water (1 L) and extracted with EtOAc (2 x 500 mL). The combined organic layers were washed with brine solution (300 mL), dried over Na2SO4 and concentrated in vacuo. The crude was purified by silica gel column chromatography to afford 44.5 g (82 %) of the compound F5. Eluent for purification: 15% ethyl acetate in w-hexane; white solid; mp 164.0 °C; [a]25D (CHC13, cl.0): +89.6°; IR (cm-1, CHC13): 3390, 2920, 2868, 2109, 1648, 1459, 1381, 1267, 1092, 1032, 756; 1H NMR (399.78 MHz, CDC13): 6 7.51 - 7.46 (m, 2H), 7.40 - 7.35 (m, 3H), 5.98 - 5.86 (m, 1H), 5.51 (s, 1H), 5.35 (dq, J = 17.3, 1.5 Hz, 1H), 5.28 - 5.22 (m, 1H), 4.92 (d, J= 3.6 Hz, 1H), 4.28 - 4.14 (m, 3H), 4.03 (ddt, J = 12.9, 6.0, 1.3 Hz, 1H), 3.86 (td, J= 10.0, 4.8 Hz, 1H), 3.70 (t, J= 10.3 Hz, 1H), 3.47 (t, J = 9.3 Hz, 1H), 3.25 (dd, J = 10.1, 3.7 Hz, 1H), 3.08 (s, 1H); 13C NMR (100.53 MHz, CDC13): 8 137.0, 133.2, 129.5, 128.5, 128.5, 126.4, 126.4, 118.2, 102.1, 97.6, 81.9, 68.9, 68.8, 68.8, 63.1, 62.6; HRMS (ESIMS): m/z calcd for C16H19N3O5 [M+Na]+: 356.1222, Found: 356.1209

[00123] Example 19: Preparation of Compound F6

[00124] To a solution of alcohol F5 (1 mmol) in anhydrous THF (2.5 mL) was added NaH (60% in mineral oil, 1.2 eq per -OH) in portions under argon atmosphere. After the evolution of hydrogen ceased, PMB-CI (1.1 eq) was added dropwise, followed by the addition of catalytic amount of tetrabutylammonium iodide and the mixture was stirred at 25 °C for 3 h. After completion, ice cold water (10 mL) was added slowly to the reaction mixture and extracted with EtOAc (2 x 10 mL), combined organic phases were dried over anhydrous Na2SO4, concentrated in vacuo to a crude residue that was purified by silica gel column chromatography using EtOAc and hexane as mobile phase to afford the corresponding ether product. F6: Eluent for purification: 12% ethyl acetate in //-hexane as a thick syrup; yield 7.85 g (81%) from 7.12 g; [a]25D (CHC13, cl.0): +47.8°; IR (cm-1, CHC13) : 2922, 2866, 2107, 1612, 1513, 1460, 1374, 1248, 1089, 1036, 999, 823, 755, 700; 1H NMR (399.78 MHz, CDC13): 8 7.55 - 7.49 (m, 2H), 7.45 - 7.37 (m, 3H), 7.35 - 7.30 (m, 2H), 6.90 - 6.85 (m, 2H), 6.00 - 5.89 (m, 1H), 5.60 (s, 1H), 5.37 (dq, J= 17.3, 1.5 Hz, 1H), 5.27 (dq, J= 10.6, 1.3 Hz, 1H), 4.95 (d, J= 3.7 Hz, 1H), 4.90 (d, J = 10.6 Hz, 1H), 4.76 (d, J = 10.6 Hz, 1H), 4.30 (dd, J= 10.2, 4.8 Hz, 1H), 4.24 (ddt, J= 12.9, 5.1, 1.4 Hz, 1H), 4.14 - 4.04 (m, 2H), 3.94 (td, J= 10.0, 4.8 Hz, 1H), 3.80 (s, 3H), 3.79 - 3.74 (m, 1H), 3.71 (t, J= 9.3 Hz, 1H), 3.42 (dd, J= 10.0, 3.7 Hz, 1H); 13C NMR (100.53 MHz, CDC13): 8 159.5, 137.3, 133.2, 130.0 (3C), 129.2, 128.4, 128.4, 126.1, 126.1, 118.3, 113.9, 113.9, 101.5, 97.5, 82.9, 76.0, 74.8, 69.0, 68.8, 63.1, 62.9, 55.3; HRMS (ESI-MS): m/z calcd for C24H27N3O6 [M+Na]+: 476.1798, Found: 476.1791

[00125] Example 20: Preparation of Compound F7

[00126] To a solution of benzylidene protected compound F6 (1.0 mmol) in 1 : 1 CH3OH:CH2C12 (2 mL) was added 0.3 equivalent of the //-toluenesulfonic acid monohydrate and the mixture was stirred at 25 °C for 1 h. After completion, the reaction was quenched with Et3N and the volatiles were evaporated under reduced pressure, the crude residue was purified by silica gel column chromatography using EtOAc and hexane as mobile phase to obtain the desired product F7. Eluent for purification: 70% ethyl acetate in //-hexane; Thick syrup; yield 5.45 g (86%) from 7.85 g; [a]25D (CHC13, cl.0): +74.0°; IR (cm-1, CHC13): 3388, 2923, 2109, 1612, 1513, 1247, 1093, 1034, 822, 759; 1H NMR (400.31 MHz, CDC13): 8 7.34 - 7.29 (m, 2H), 6.91 - 6.87 (m, 2H), 5.93 (dddd, J= \1A, 10.4, 6.1, 5.3 Hz, 1H), 5.34 (dq, J= 17.2, 1.6 Hz, 1H), 5.24 (dq, J= 10.4, 1.3 Hz, 1H), 4.93 (d, J= 3.5 Hz, 1H), 4.88 (d, J = 10.9 Hz, 1H), 4.68 (d, J= 10.9 Hz, 1H), 4.20 (ddt, J= 13.0, 5.2, 1.5 Hz, 1H), 4.03 (ddt, J= 13.0, 6.2, 1.3 Hz, 1H), 3.83 (dd, J= 10.2, 8.5 Hz, 1H), 3.79 (s, 3H), 3.79 - 3.76 (m, 2H), 3.67 (dt, J= 9.7, 3.6 Hz, 1H), 3.63 - 3.57 (m, 1H), 3.28 (dd, J = 10.2, 3.5 Hz, 1H), 2.78 (s, 1H), 2.23 (s, 1H); 13C NMR (100.67 MHz, CDC13): 8 159.6, 133.3, 130.2, 129.9, 129.9, 118.3, 114.2, 114.2, 97.0, 79.8, 74.9, 71.5, 70.9, 68.7, 63.2, 62.1, 55.4; HRMS (ESI-MS): m/z calcd for C17H23N3O6 [M+Na]+: 388.1485, Found: 388.1485

[00127] Example 21: Preparation of Compound F8

[00128] A solution of the 4,6-diol F7 (5.45 g, 31.15 mmol) in anhydrous CH2C12 (50 mL) was added 9.0 eq of Et3N and the benzoic anhydride (1.2 eq) was added slowly at 0 °C under argon atmosphere. The reaction mixture was stirred at 25 °C for 12 h, quenched by adding methanol (5 mL), volatiles were evaporated under vacuum and the residue was purified by silica gel column chromatography using 12% ethyl acetate in //-hexane as a mobile phase to afford F8 (5.86 g, 86%) as a thick syrup; [a]25D (CHC13, cl.0): +74.0°; IR (cm-1, CHC13): 3465, 2919, 2106, 1717, 1611, 1514, 1455, 1271, 1109, 1033, 930, 822, 756, 713; 1H NMR (399.78 MHz, CDC13): 8 8.04 (dt, J= 8.4, 1.6 Hz, 2H), 7.60 - 7.55 (m, 1H), 7.46 - 7.41 (m, 2H), 7.37 - 7.31 (m, 2H), 6.92 - 6.87 (m, 2H), 5.94 (dddd, J= 16.8, 10.3, 6.1, 5.4 Hz, 1H), 5.34 (dq, J= VIA, 1.5 Hz, 1H), 5.24 (dq, J= 10.5, 1.4 Hz, 1H), 4.97 (d, = 3.6 Hz, 1H), 4.87 (d, J= 10.7 Hz, 1H), 4.76 (d, J= 10.7 Hz, 1H), 4.71 (dd, J= 12.2, 4.4 Hz, 1H), 4.47 (dd, J = 12.2, 2.1 Hz, 1H), 4.23 (ddt, J = 12.9, 5.2, 1.4 Hz, 1H), 4.08 (ddt, J = 13.1, 6.3, 1.3 Hz, 1H), 3.94 (ddd, J= 10.0, 4.3, 2.1 Hz, 1H), 3.88 (dd, J= 10.2, 8.7 Hz, 1H), 3.79 (s, 3H), 3.57 (td, J = 9.9, 3.6 Hz, 1H), 3.34 (dd, J = 10.2, 3.5 Hz, 1H), 2.91 (d, J = 3.4 Hz, 1H); 13C NMR (100.53 MHz, CDC13): 8 167.2, 159.7, 133.5, 133.3, 130.1, 130.0, 130.0, 129.9, 129.9, 129.6, 128.6, 128.6, 118.4, 114.2, 114.2, 97.0, 79.5, 75.1, 70.8, 70.4, 68.8, 63.5, 63.1, 55.4; HRMS (ESI-MS): m/z calcd for C24H27N3O7 [M+Na]+: 492.1746, Found: 492.1743

[00129] Example 22: Preparation of Compound Hl

[00130] This compound was prepared following the above delineated procedure for F6. Eluent for purification: 10% ethyl acetate in //-hexane; white solid; yield 9.9 g (87%) from 9.0 g as a solid; mp = 174.5 °C; [a]25D (CHC13, cl.0): +53.3°; IR (cm-1, CHC13): 2919, 2868, 2107, 1457, 1375, 1268, 1088, 997, 752, 698; 1H NMR (399.78 MHz, CDC13): 8 7.57 - 7.52 (m, 2H), 7.46 - 7.40 (m, 5H), 7.39 - 7.30 (m, 3H), 5.97 (ddt, J= 16.3, 10.7, 5.7 Hz, 1H), 5.62 (s, 1H), 5.43 - 5.36 (m, 1H), 5.29 (d, J = 10.4 Hz, 1H), 5.00 (d, J= 11.0 Hz, 1H), 4.98 (d, J= 3.7 Hz, 1H), 4.85 (d, J= 11.0 Hz, 1H), 4.32 (dd, J= 10.2, 4.8 Hz, 1H), 4.26 (dd, J = 12.9, 5.2 Hz, 1H), 4.16 (t, J = 9.5 Hz, 1H), 4.09 (dd, J= 12.9, 6.1 Hz, 1H), 3.97 (td, J = 10.0, 4.8 Hz, 1H), 3.82 - 3.77 (m, 1H), 3.77 - 3.72 (m, 1H), 3.45 (dd, J = 9.9, 3.6 Hz, 1H); 13C NMR (100.53 MHz, CDC13): 8 137.9, 137.3, 133.2, 129.1, 128.5, 128.5, 128.4, 128.4, 128.3, 128.3, 127.9, 126.1, 126.1, 118.3, 101.5, 97.5, 82.9, 76.3, 75.1, 68.9, 68.8, 63.1, 62.9; HRMS (ESI-MS): m/z calcd for C23H25N3O5 [M+Na]+: 446.1692, Found: 446.1688 [00131] Example 23: Preparation of Compound H2

[00132] This compound was prepared following the above delineated procedure for F7. Eluent for purification: 40% ethyl acetate in //-hexane; thick syrup; yield 7.0 g (89%) from 9.9 g; [a]25D (CHC13, cl.0): +54.0°; IR (cm-1, CHC13): 3383, 2923, 2108, 1454, 1361, 1267, 1032, 754, 699; 1H NMR (399.78 MHz, CDC13): 8 7.40 - 7.26 (m, 5H), 5.96 - 5.84 (m, 1H), 5.33 (dq, J= 17.3, 1.6 Hz, 1H), 5.25 - 5.19 (m, 1H), 4.91 - 4.86 (m, 2H), 4.80 (d, J = 11.1 Hz, 1H), 4.19 - 4.12 (m, 1H), 4.02 - 3.95 (m, 1H), 3.86 - 3.81 (m, 1H), 3.79 - 3.65 (m, 3H), 3.62 (d, J = 6.0 Hz, 2H), 3.26 (dd, J = 10.2, 3.6 Hz, 1H), 3.02 (s, 1H); 13C NMR (100.53 MHz, CDC13): 8 137.9, 133.2, 128.6, 128.6, 128.1(3C), 118.1, 96.9, 79.9, 75.2, 71.6, 70.4, 68.5, 62.9, 61.4. 3

[00134] A solution of the 4,6-diol H2 (2.32 g, 6.92 mmol) in anhydrous CH2C12 (40 mL) was added 9.0 eq of Et3N and the acetic anhydride (1.2 eq) dropwise at 0 °C under argon atmosphere. The reaction mixture was stirred at 25 °C for 12 h, quenched by adding methanol (4 mL), volatiles were evaporated and the residue was purified by silica gel column chromatography using 10% ethyl acetate in //-hexane as mobile phase to afford compound H3 (2.2 g, 84%) as a thick syrup; [a]25D (CHC13, cl.0): +60.8°; IR (cm-1, CHC13): 3452, 2920, 2108, 1737, 1455, 1367, 1245, 1097, 1037, 921, 747, 7O1;1H NMR (400.31 MHz, CDC13): 8 7.42 - 7.29 (m, 5H), 5.94 (dddd, J = 17.1, 10.4, 6.2, 5.3 Hz, 1H), 5.35 (dq, J = 17.2, 1.6 Hz, 1H), 5.25 (dq, J = 10.4, 1.3 Hz, 1H), 4.96 (d, J = 3.6 Hz, 1H), 4.93 (d, J = 11.0 Hz, 1H), 4.82 (d, J= 11.0 Hz, 1H), 4.51 (dd, J= 12.3, 4.1 Hz, 1H), 4.23 - 4.16 (m, 2H), 4.06 (ddt, J= 12.9, 6.2, 1.3 Hz, 1H), 3.87 (dd, J = 10.2, 8.7 Hz, 1H), 3.81 (ddd, J = 10.0, 4.0, 2.3 Hz, 1H), 3.49 (td, J = 9.9, 3.4 Hz, 1H), 3.33 (dd, J= 10.2, 3.6 Hz, 1H), 2.75 (d, J= 3.5 Hz, 1H), 2.11 (s, 3H); 13C NMR (100.53 MHz, CDC13): 8 171.9, 138.0, 133.2, 128.8, 128.8, 128.3 (3C), 118.4, 97.0, 79.7, 75.4, 70.7, 70.2, 68.8, 63.0, 63.0, 21.0; HRMS (ESI-MS): m/z calcd for C18H23N3O6 [M+Na]+: 400.1485, Found: 400.1489

[00135] Example 25: Preparation of Compound DI

[00136] To a solution of the 4,6-diol compound H2 (1.0 mmol) and Et3N (5 eq) in anhydrous CH2C12 (5 mL) was added 0.5 equivalent of DMAP. The TBDPSCI (1.2 eq) was added drop-wise with stirring under argon atmosphere and the reaction mixture was stirred at 25 °C for 15 h. Ice-cold water (30 mL) was added to the reaction mixture and extracted with CH2C12 (3x20 mL), organic layer was washed with brine solution (2 x 50 mL), dried over Na2SO4 and concentrated in vacuo. The crude product was purified by flash silica gel column chromatography using EtOAc and hexane as a mobile phase to obtain the desired product DI. Eluent for purification: 8% ethyl acetate in //-hexane; Thick syrup; yield 10.03 g (98%) from 6.0 g; [a]25D (CHC13, cl.0): +40.5°; IR (cm-1, CHC13): 3382, 3069, 2932, 2861, 2106, 1465, 1355, 1268, 1103, 1049,752, 701; 1H NMR (399.78 MHz, CDC13): 8 7.73 - 7.69 (m, 4H), 7.47 - 7.31 (m, 11H), 6.01 - 5.85 (m, 1H), 5.34 (dq, J= 17.3, 1.5 Hz, 1H), 5.29 - 5.18 (m, 1H), 4.96 - 4.91 (m, 2H), 4.87 (d, J= 11.1 Hz, 1H), 4.19 (ddt, J= 12.9, 5.1, 1.4 Hz, 1H), 4.07 - 4.00 (m, 1H), 3.92 - 3.87 (m, 3H), 3.76 - 3.71 (m, 2H), 3.34 (dd, J = 10.2, 3.6 Hz, 1H), 2.55 (d, J= 1.9 Hz, 1H), 1.09 (s, 9H); 13C NMR (100.53 MHz, CDC13): 8

138.3, 135.8, 135.8, 135.7, 135.7, 133.4, 133.2, 133.0, 130.0, 130.0, 128.7, 128.7, 128.3,

128.3, 128.1, 127.9(4C), 118.1, 96.7, 80.1, 75.3, 72.7, 71.2, 68.4, 64.4, 63.0, 27.0(3C), 19.4; HRMS (ESI-MS): m/z calcd for C32H39N3O5Si[M+H]+: 574.2737, Found: 574.2726

[00137] Example 26: Preparation of Compound D2

TBDPSO— \ NaH (1.1 eq) TBDPSO-

BnBr (1.2 eq) BnO--^ -O

Bn°- ^, * ^, T _{RT 3h 93} o _/o BnO-^--*^

N ₃ OAII - ► ^N 3OAII

D1 D2

[00138] This compound was prepared by following the above described procedure for F6. Eluent for purification: 6% ethyl acetate in //-hexane; Thick syrup; yield 8.6 g (93%) from 8.0 g; [a]25D (CHC13, cl.0): +55.9°; IR (cm-1, CHC13): 3029, 2932, 2861, 2107, 1461, 1268, 1151, 1093, 1060, 752, 700; 1H NMR (399.78 MHz, CDC13): 8 7.76 - 7.70 (m, 4H), 7.48 - 7.41 (m, 5H), 7.41 - 7.39 (m, 2H), 7.39 - 7.37 (m, 2H), 7.37 - 7.32 (m, 3H), 7.32 - 7.30 (m, 2H), 7.21 (dd, J= 6.7, 2.9 Hz, 2H), 5.94 (dddd, J= 16.7, 10.3, 6.2, 5.3 Hz, 1H), 5.34 (dq, J =

17.2, 1.6 Hz, 1H), 5.24 (dq, J = 10.5, 1.1 Hz, 1H), 5.02 (d, J = 3.6 Hz, 1H), 4.94 - 4.89 (m, 3H), 4.71 (d, J = 10.8 Hz, 1H), 4.21 (ddt, J = 12.9, 5.1, 1.4 Hz, 1H), 4.11 - 4.03 (m, 2H), 3.96 (dd, J = 11.2, 2.9 Hz, 1H), 3.91 (dd, J = 11.2, 0.8 Hz, 1H), 3.82 - 3.78 (m, 2H), 3.46 (dd, J = 10.2, 3.6 Hz, 1H), 1.10 (s, 9H); 13C NMR (100.53 MHz, CDC13): 8 138.1, 138.0(3C), 135.7, 135.7, 133.6, 133.5, 133.2, 129.8, 129.8, 128.6(4C), 128.4, 128.4, 128.1, 127.9(3C), 127.8, 127.8, 127.7, 127.7, 118.1, 96.6, 80.6, 78.5, 75.8, 75.3, 72.2, 68.3, 63.8, 62.6, 26.9(3C), 19.4; HRMS (ESI-MS): m/z calcd for C39H45N3O5Si[M+Na]+: 664.3206, Found: 664.3215.

[00139] Example 27: Preparation of Compound D3

TBDPSO— \ PdCI ₂ (0.15 eq) TBDPSO-, Bn0-V^--0 MeOH-CH ₂ CI ₂ BnO-y^-O RT, 4-8h, 85% BnO- *T*

^N 3OAII N ₃ OH

D2 D3

[00140] To a biphasic solution of the alkyl glycoside D2 (1.0 mmol) in 3: 1 CH3OH:CH2C12 (20 mL) was added 0.15 equivalent of PdC12 and the reaction mixture was stirred for 4-8 h at 25 °C, the reaction was quenched by adding excess of Et3N and filtered through a bed of Celite®. The filtrate concentrated in vacuo and the crude residue was purified by silica gel column chromatography using ethyl acetate and //-hexane as a mobile phase to obtain desired hemiacetal D3. Eluent for purification: 12% ethyl acetate in //-hexane; Thick syrup; yield 6.8 g (85%) from 8.5 g; [a]25D (CHC13, cl.0): -8.7°; IR (cm-1, CHC13): 3045, 2936, 2859, 2106, 1471, 1268, 1105, 754, 7O2;1H NMR (400.31 MHz, CDC13)a:p isomers(1.5: l): 8 7.73 - 7.64 (m, 8H), 7.42 - 7.26 (m, 28H), 7.22 - 7.15 (m, 4H), 5.26 (t, J = 3.3 Hz, 1H), 4.93 - 4.79 (m, 6H), 4.70 (dd, J= 28.2, 10.9 Hz, 2H), 4.45 (dd, J = 7.9, 5.2 Hz, 1H), 4.06 - 3.82 (m, 8H), 3.77 - 3.72 (m, 1H), 3.47 - 3.40 (m, 2H), 3.36 - 3.26 (m, 2H), 2.96 (d, J= 3.0 Hz, 1H), 1.06 (s, 18H); 13C NMR (100.67 MHz, CDC13) (a:p isomers(1.5:l)): 8

138.2, 138.0(3C), 136.1, 136.1, 136.0, 136.0, 135.7(4C), 133.8, 133.7, 133.2, 133.2, 129.8(4C), 128.6(8C), 128.4(2C), 128.3(2C), 128.1(2C), 127.9(3C), 127.8(5C), 127.7(6C),

96.2, 92.2, 83.2, 80.2, 78.4, 77.6, 76.2, 75.8, 75.8, 75.2, 75.2, 72.1, 67.8, 64.4, 62.9, 62.7, 27.0(6C), 19.5, 19.4 [00141] Example 28: Preparation of Compound D4

[00142] To a solution of glycosylhemiacetal D3 (1.0 mmol) in anhydrous CH2C12 (5 mL) was added DMAP (1.5 eq) and ethynyl cyclohexyl (4-nitrophenyl) carbonate (1.2 eq), the reaction mixture was stirred at 25 °C for 3 h. After complete consumption of the starting hemiacetal, the reaction mixture was concentrated in vacuo and purified by silica gel column chromatography using EtOAc and hexane as a mobile phase to obtain the desired carbonate donor D4. Eluent for purification: 8% ethyl acetate in //-hexane; Thick syrup; yield 6.2 g (92%) from 6.7 g; [a]25D (CHC13, cl.0): +5.3°; IR (cm- 1, CHC13): 3280, 3032, 2936, 2862, 2111, 1765, 1765, 1457, 1357, 1269, 1096, 1018, 909, 754, 700; 1H NMR (400.31 MHz, CDC13): 8 7.70 (dd, J= 16.0, 6.8 Hz, 8H), 7.45 - 7.30 (m, 28H), 7.26 - 7.18 (m, 4H), 6.16 (d, J= 3.4 Hz, 1H), 5.36 (d, J= 7.6 Hz, 1H), 4.92 (d, J= 9.6 Hz, 6H), 4.77 (t, J= 11.1 Hz, 2H), 4.05 (t, J = 9.4 Hz, 1H), 4.00 - 3.84 (m, 7H), 3.67 - 3.56 (m, 3H), 3.45 (d, J = 9.6 Hz, 1H), 2.67 (s, 1H), 2.64 (s, 1H), 2.28 - 2.14 (m, 4H), 2.04 - 1.84 (m, 4H), 1.78 - 1.62 (m, 8H), 1.58 - 1.48 (m, 2H), 1.45 - 1.34 (m, 2H), 1.07 (s, 18H); 13C NMR (100.67 MHz, CDC13): 8 151.1, 151.0, 138.0, 138.0, 137.8, 137.7, 136.0(4C), 135.7(4C), 133.6, 133.5, 133.0, 132.9, 129.8(3C), 129.7, 128.7(4C), 128.6(4C), 128.5(2C), 128.4(2C), 128.2(2C), 128.0, 127.9(9C), 127.8, 127.7(3C), 96.0, 94.3, 83.3, 82.7, 82.6, 80.7, 78.8, 78.4, 77.6, 77.3, 76.6, 76.1, 76.0, 75.5, 75.3(3C), 74.3, 65.1, 63.2, 62.2, 62.0, 37.0, 36.8(2C), 36.7, 27.0(3C), 26.9(3C), 25.1(2C), 22.6(4C), 19.5, 19.4; HRMS (ESI-MS): m/z calcd for C45H51N3O7Si[M+Na]+: 796.3394, Found: 796.3386.

[00143] Example 29: Preparation of Compound El

[00144] To the compound G2 (74 g, 211.18 mmol) in a IL round bottom flask was added 90% aqueous trifluoroacetic acid (320 mL) and the reaction mixture was stirred for 15 min at 25 °C. The solvent was evaporated under reduced pressure and the residue was co-evaporated twice with water and twice with toluene. Crude was triturated in minimum quantity of the 10% ethyl acetate in hexane, washed with hexane and the trace solvent was removed by applying high vacuum. The crude product El was used as such for next reaction.

[00145] Example 30: Preparation of Compound E2

[00146] Compound El was dissolved in anhydrous allyl alcohol (50 eq) and the mixture cooled to 0 °C, acetyl chloride (2.5 eq) was added dropwise under argon atmosphere, the reaction mixture was stirred at 0 °C for Ih, refluxed at 80 °C for 12-16 h. After complete conversion, the reaction was quenched by adding excess of Et3N and the volatile components were removed under vacuum. The crude residue was purified by silica gel column chromatography using 50% ethyl acetate in //-hexane as mobile phase to afford compound E2 (49.5 g, 76%, over two steps) as a thick syrup; [a]25D (CHC13, cl.0): +63.1°; IR (cm-1, CHC13): 3394, 1923, 1643, 1362, 1216, 1028, 927, 746, 700; IH NMR (399.78 MHz, CDC13): 8 7.38 - 7.25 (m, 10H), 5.97 - 5.85 (m, 2H), 5.30 (ddq, J = 17.3, 3.0, 1.5 Hz, 2H), 5.24 - 5.19 (m, 2H), 5.0-4.93 (d, J= 11.5 Hz, 2H), 4.87 (d, J= 3.5 Hz, IH), 4.77-4.71 (d, J = 11.6 Hz, 2H), 4.35 (dt, J= 5.4, 1.4 Hz, IH), 4.32 (d, J= 7.7, IH), 4.19 (ddt, J= 12.8, 5.3, 1.4 Hz, IH), 4.13 - 4.07 (ddt, IH), 4.04 - 3.98 (m, IH), 3.85 - 3.81 (m, IH), 3.76 (d, J= 3.5 Hz, 2H), 3.72 (m, IH), 3.66 - 3.54 (m, 5H), 3.53 - 3.47 (m, IH), 3.39 (t, J= 9.0 Hz, IH), 3.32 - 3.27 (m, IH), 2.91 (s, IH), 2.71 (s, IH), 2.47 - 2.28 (m, 2H), 2.26 (m, 2H);13C NMR (100.53 MHz, CDC13): 8 138.6, 138.6, 133.7, 133.6, 128.7(4C), 128.1(5C), 128.0, 118.3, 118.3, 102.0, 97.8, 83.8, 82.9, 75.4, 75.1, 74.9, 74.4, 72.8, 71.4, 70.6, 70.0, 70.0, 68.7, 62.4, 62.2; HRMS (ESI-MS): m/z calcd for C16H22O6 [M+Na]+: 333.1314, Found: 333.1316.

[00147] Example 31: Preparation of Compound E3

[00148] To a solution of the compound E2 (30 g, 96.67 mmol) in anhydrous DMF (150 mL) was added benzaldehyde dimethyl acetal (17.41 mL, 116 mmol), followed by the camphorsulfonic acid (4.49 g, 19.33 mmol) was added portion-wise under argon atmosphere and the reaction mixture stirred at 25 °C for 4 h. Ice-cold saturated aq NaHCO3 solution (150 mL) and water (150 mL) were added to neutralize the reaction and extracted with EtOAc (3 x 100 mL), organic layer was washed with brine (3 x 100 mL), dried over anhydrous Na2SO4 and concentrated in vacuo. The product was precipitated by stirring crude residue in the combination of CH2C12-hexane solvent mixture and the residue was washed with hexane, dried over high vacuum to afford 25.5 g of white solid. The filtrate was evaporated and purified by column chromatography resulting in the overall 28.9 g (75%) of the compound E3. Eluent for purification: 25% ethyl acetate in w-hexane; white solid; mp 143.1 °C; [a]25D (CHC13, cl.O): +90.4°; IR (cm-1, CHC13): 3432, 3025, 2925, 2869, 1449, 1367, 1217, 1076, 1032, 748, 694; 1H NMR (400.31 MHz, CDC13): 8 7.54 - 7.48 (m, 2H), 7.44 - 7.36 (m, 5H), 7.36 - 7.27 (m, 3H), 5.94 (dddd, J = 16.8, 10.4, 6.3, 5.4 Hz, 1H), 5.58 (s, 1H), 5.33 (dq, J = 17.2, 1.5 Hz, 1H), 5.25 (dd, J= 10.4, 1.3 Hz, 1H), 5.00 - 4.95 (m, 2H), 4.82 (d, J= 11.6 Hz, 1H), 4.30 (dd, J= 10.2, 4.8 Hz, 1H), 4.24 (ddt, J= 12.8, 5.4, 1.4 Hz, 1H), 4.08 (ddt, J= 12.8, 6.4, 1.2 Hz, 1H), 3.94 - 3.88 (m, 1H), 3.86 (d, J= 9.2 Hz, 1H), 3.76 (t, J= 10.3 Hz, 2H), 3.66 (t, J = 9.3 Hz, 1H), 2.38 (s, 1H);13C NMR (100.67 MHz, CDC13): 8 138.6, 137.4, 133.5,

129.1, 128.5, 128.5, 128.4, 128.4, 128.1, 128.1, 127.8, 126.1, 126.1, 118.4, 101.4, 98.1, 82.0,

79.1, 75.0, 72.5, 69.1, 68.9, 62.9; HRMS (ESI-MS): m/z calcd for C23H26O6 [M+Na]+: 421.1627, Found: 421.1628.

[00149] Example 32: Preparation of Compound E4

Ph^OTX _n BzCI (1.2 eq) Ph^OAX _n

Py. DMAP (cat)

^Bn0 ^T ^H j ^O j RT, OAII _ ^2h - ^92% ► ^Bn0- ^ B ^Z r O OAII

E3 E4

[00150] A solution of the compound E3 (20 g, 50.19 mmol) in anhydrous pyridine (100 mL) was cooled to 0°C and the benzoyl chloride (1.2 eq) was added drop-wise under argon atmosphere, catalytic amount of DMAP was added. The reaction mixture was gradually warmed up to 25°C and stirred for 2 h. After completion, ice cooled water (500mL) was added and extracted with EtOAc (2 x 250 mL). The organic layer was washed with aqueous 1A HC1 (3 x 300 mL) and brine solution (500 mL), dried over anhydrous Na2SO4, concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 10% ethyl acetate in //-hexane as mobile phase to afford 23.2 g (92%) of the compound E4 as a white solid, mp 93.6 °C; [a]25D (CHC13, cl.O): +146.6°; IR (cm-1, CHC13): 3024, 2930, 2867, 1727, 1601, 1453, 1370, 1270, 1217, 1096, 997, 752, 7O2;1H NMR (400.31 MHz, CDC13): 8 8.16 - 8.09 (m, 2H), 7.66 (tt, J = 7.0, 1.3 Hz, 1H), 7.62 - 7.57 (m, 2H), 7.55 - 7.43 (m, 5H), 7.34 - 7.29 (m, 2H), 7.29 - 7.20 (m, 3H), 5.88 (dddd, J = VIA, 10.5, 5.9, 5.2 Hz, 1H), 5.69 (s, 1H), 5.36 - 5.27 (m, 2H), 5.26 - 5.17 (m, 2H), 4.97 (d, J = 11.8 Hz, 1H), 4.85 (d, J= 11.8 Hz, 1H), 4.39 (dd, J= 10.2, 4.8 Hz, 1H), 4.32 (t, J= 9.4 Hz, 1H), 4.25 (ddt, J= 13.2, 5.1, 1.5 Hz, 1H), 4.11 - 4.03 (m, 2H), 3.88 (td, J = 9.9, 9.4, 2.4 Hz, 2H);13C NMR (100.67 MHz, CDC13): 8 166.0, 138.4, 137.5, 133.6, 133.3, 130.0, 130.0,

129.8, 129.1, 128.5, 128.5, 128.4, 128.4, 128.3, 128.3, 128.0, 128.0, 127.6, 126.2, 126.2, 117.7, 101.5, 96.3, 82.4, 76.1, 74.9, 73.6, 69.1, 68.8, 62.7; HRMS (ESI-MS): m/z calcd for C30H3007 [M+Na]+: 525.1889, Found: 525.1879.

[00151] Example 33: Preparation of Compound E5

[00152] This compound was prepared by following the above mentioned procedure for F7. Eluent for purification: 50% ethyl acetate in //-hexane; Thick syrup; yield 17.5 g (91%) from 23.2 g; [a]25D (CHC13, cl.0): +145.8°; IR (cm-1, CHC13): 3436, 3022, 2929, 1726, 1601, 1451, 1365, 1272, 1218, 1103, 1033, 749, 708; 1H NMR (400.31 MHz, CDC13): 8 8.10 - 8.03 (m, 2H), 7.58 (tt, J = 7.0, 1.3 Hz, 1H), 7.48 - 7.42 (m, 2H), 7.27 - 7.17 (m, 5H), 5.90 - 5.72 (m, 1H), 5.25 (dq, J= 17.2, 1.6 Hz, 1H), 5.18 (d, J = 3.7 Hz, 1H), 5.11 (dq, J= 10.4, 1.3 Hz, 1H), 5.07 (dd, J= 9.9, 3.7 Hz, 1H), 4.85 (d, J = 11.5 Hz, 1H), 4.74 (d, J = 11.5 Hz, 1H), 4.18 (ddt, J= 13.3, 5.1, 1.5 Hz, 1H), 4.11 - 4.04 (m, 1H), 3.98 (ddt, J = 13.3, 5.9, 1.4 Hz, 1H), 3.87 - 3.81 (m, 2H), 3.81 - 3.72 (m, 2H), 3.16 (s, 1H), 2.55 (s, 1H);13C NMR (100.67 MHz, CDC13): 8 166.0, 138.2, 133.6, 133.3, 129.8, 129.8, 129.7, 128.5(4C), 127.9,

127.9, 127.7, 117.5, 95.5, 79.8, 75.3, 74.0, 71.3, 70.4, 68.5, 62.1; HRMS (ESI-MS): m/z calcd for C23H26O7 [M+Na]+: 437.1576, Found: 437.1569

[00153] Example 34: Preparation of Compound E6

[00154] To a biphasic solution of the 4,6-diol E5(l mmol) in 2: 1 CH2C12-water (10 mL) was added BAIB (2.5 eq) and TEMPO (0.2 eq) simultaneously, stirred vigorously at 25 °C. After 3 h, the reaction was quenched by the addition of a saturated solution of Na2SO3 and extracted by CH2C12 (3 x 10 mL),the combined organic phases were washed with brine (10 mL), dried over Na2SO4 and concentrated in vacuo. The crude product E6 was forwarded as such for next reaction. [00155] Example 35: Preparation of Compound E7

[00156] Compound E6 was dissolved in anhydrous DMF (5 mL) and added 1.5 equivalent of K2CO3. After stirring for 15 min, iodomethane (2.0 eq) was added dropwise under argon atmosphere and stirred for 8h at 25 °C in a dark place. After complete consumption, the reaction was arrested by additing saturated solution of Na2SO3, brine (5 mL) and water (10 mL); and extracted with EtOAc (2 x 10 mL). The combined organic phase was washed with brine, dried over anhydrous Na2SO4, concentrated under reduced pressure. The crude residue was purified by column chromatography using ethyl acetate and //-hexane as mobile phase to obtain the desired product E7. Eluent for purification: 20% ethyl acetate in //-hexane; thick syrup; yield 6.35 g (74%, over two steps) from 8.0 g; [a]25D (CHC13, cl.0): +143.6°; IR (cm-1, CHC13): 3467, 3017, 2956, 1731, 1602, 1448, 1364, 1269, 1213, 1101, 1050, 925, 748, 7O9;1H NMR (400.31 MHz, CDC13): 8 8.11 - 8.05 (m, 2H), 7.61 (t, J = 7.4 Hz, 1H), 7.48 (t, J= 7.7 Hz, 2H), 7.31 - 7.22 (m, 5H), 5.91 - 5.78 (m, 1H), 5.34 - 5.27 (m, 2H), 5.17 (dd, J= 10.5, 1.3 Hz, 1H), 5.13 (dd, J= 9.9, 3.7 Hz, 1H), 4.86 (s, 2H), 4.33 (d, J= 9.8 Hz, 1H), 4.26 (ddt, J= 13.2, 5.0, 1.4 Hz, 1H), 4.15 - 4.09 (m, 1H), 4.09 - 3.98 (m, 2H), 3.87 (s, 3H), 3.16 (s, 1H); 13C NMR (100.67 MHz, CDC13): 8 170.7, 165.9, 138.3, 133.4, 133.2,

129.9, 129.9, 129.7, 128.6, 128.6, 128.5, 128.5, 128.0, 128.0, 127.8, 118.0, 95.9, 78.6, 75.4,

72.9, 72.4, 70.6, 69.1, 52.9; HRMS (ESI-MS): m/z calcd for C24H26O8 [M+Na]+: 465.1525, Found: 465.1519.

[00157] Example 36: Preparation of Compound E8

[00158] This compound was prepared by following procedure described for the compound Gil. Eluent for purification: 5% ethyl acetate in //-hexane; Thick syrup; yield 4.1 g (93%) from 3.5 g; [a]25D (CHC13, cl.0): +145.7°; IR (cm-1, CHC13): 2938, 2860, 1753, 1725, 1601, 1453, 1328, 1264, 1102, 1051, 842, 777, 744, 710; 1H NMR (399.78 MHz, CDC13): 8 7.91 - 7.86 (m, 2H), 7.45 - 7.40 (m, 1H), 7.32 - 7.26 (m, 2H), 7.09 - 7.01 (m, 5H), 5.77 - 5.65 (m, 1H), 5.17 (dq, J= 17.3, 1.6 Hz, 1H), 5.14 - 5.08 (m, 2H), 5.03 (dq, J= 10.6, 1.3 Hz, 1H), 4.74 (d, J= 11.2 Hz, 1H), 4.66 (d, J= 11.3 Hz, 1H), 4.24 - 4.18 (m, 1H), 4.13 (ddt, J = 13.2, 5.1, 1.5 Hz, 1H), 3.99 - 3.87 (m, 3H), 3.69 (s, 3H), 0.78 (s, 9H), -0.09 (s, 3H), -0.10 (s, 3H); 13C NMR (100.53 MHz, CDC13): 8 169.8, 165.8, 138.2, 133.4, 133.3, 129.8, 129.8, 129.6, 128.5, 128.5, 128.2, 128.2, 127.4, 127.3, 127.3, 118.0, 99.0, 78.0, 75.3, 73.9, 72.6,

72.6, 69.0, 52.5, 25.9(3C), 18.0, -3.9, -5.1; HRMS (ESI-MS): m/z calcd for C30H4008Si[M+Na]+: 579.2390, Found: 579.2394.

[00159] Example 37: Preparation of Compound E9

[00160] This compound was prepared by following the above described procedures for D3. Eluent for purification: 20% ethyl acetate in //-hexane; Thick syrup; yield 1.9 g (82%) from 2.5 g; [a]25D (CHC13, cl.0): +118.2°; IR (cm-1, CHC13): 3480, 2948, 2859, 1726, 1602, 1451, 1266, 1102, 1061, 841, 751, 711;1H NMR (399.78 MHz, CDC13): 8 7.98 (d, J = 7.4 Hz, 2H), 7.53 (t, J = 7.4 Hz, 1H), 7.38 (t, J= 7.7 Hz, 2H), 7.21 - 7.11 (m, 5H), 5.58 (t, J = 3.9 Hz, 1H), 5.19 - 5.11 (m, 1H), 4.85 - 4.73 (m, 2H), 4.51 (d, J= 8.3 Hz, 1H), 4.04 (p, J= 8.1 Hz, 2H), 3.78 - 3.71 (m, 4H), 0.86 (s, 9H), -0.01 (s, 3H), -0.02 (s, 3H); 13C NMR (100.53 MHz, CDC13): 8 170.0, 166.0, 138.0, 133.4, 129.8, 129.8, 129.5, 128.5, 128.5, 128.2, 128.2, 127.5, 127.4, 127.4, 90.7, 79.1, 75.1, 73.8, 72.7, 72.2, 52.5, 25.8(3C), 18.0, -4.0, -5.2; HRMS (ESI-MS): m/z calcd for C27H36O8Si[M+Na]+: 539.2077, Found: 539.2080

[00161] Example 38: Preparation of Compound E10

[00162] Compound E10 (a:|J ratio 4:1) was prepared by following the above described procedures for D4. Eluent for purification: 5% ethyl acetate in //-hexane; Thick syrup; yield 2.1 g (86%) from 1.9 g; [a]25D (CHC13, c 1.0): +72.9°; IR (cm-1, CHC13): 3279, 2941, 2861, 2117, 1760, 1451, 1271, 1243, 1149, 1100, 1043, 1010, 899, 844, 754, 708; 1H NMR (399.78 MHz, CDC13): 8 7.97 - 7.90 (m, 4H), 7.57 - 7.49 (m, 2H), 7.42 - 7.34 (m, 4H), 7.18 - 7.10 (m, 10H), 6.35 - 5.82 (m, 2H), 5.45 - 5.33 (m, 2H), 4.82 - 4.64 (m, 4H), 4.45 - 4.02 (m, 6H), 3.78 (s, 6H), 2.42 (s, 2H), 2.21 - 1.96 (m, 4H), 1.95 - 1.73 (m, 4H), 1.66 - 1.38 (m, 10H), 1.35 - 1.23 (m, 2H), 0.86 (s, 18H), -0.01 (d, 12H); 13C NMR (100.53 MHz, CDC13): 8 168.8, 168.4, 165.3, 165.0, 151.1, 150.8, 137.9, 137.5, 133.4, 133.4, 130.0, 130.0, 129.9,

129.9, 129.4, 129.2, 128.4(4C), 128.2(4C), 127.8, 127.8, 127.6, 127.5, 127.4, 127.4, 95.0, 93.1, 82.5, 82.3, 81.7, 79.5, 18.0, 18.0, -3.9, -4.1, -5.1, -5.2; HRMS (ESI-MS): m/z calcd for C36H46O10Si[M+Na]+:

[00163] 689.2758, Found: 689.2758. 78.8, 78.5, 77.5, 75.5, 75.3, 75.1, 74.7, 74.6, 72.5,

72.3, 72.0, 71.7, 52.6, 52.6, 36.7, 36.7, 36.6, 36.5, 25.8(6C), 25.0, 24.9, 22.6, 22.6, 22.4, 22.3,

[00164] Example 39: Preparation of Compound EFl

[00165] To a solution of glycosyl donor E10 (1.0 eq) and acceptor F8 (0.8 eq) in anhydrous CH2C12 (5 ml/mmol) was added freshly activated 4A MS powder (0.400 g/mmol) at 25 °C under argon atmosphere. After 15 min of vigorous stirring at 25 °C, chloro[tris(2,4- di-t-butyl phenyl)phosphite]gold(I) (8mol%) and AgOTf (8mol%) were added simultaneously to the reaction mixture and stirred for 15 min. After completion, the reaction mixture was quenched by adding excess of Et3N and filtered through a bed of Celite®, the filtrate was concentrated in vacuo and the crude residue was purified by silica gel column chromatography. Eluent for purification: 8% ethyl acetate in //-hexane; white solid; yield 2.8 g (91%) from 1.5 g; [a]25D (CHC13, cl.0): +88.2°; IR (cm-1, CHC13): 3028, 2948, 2862, 2109, 1733, 1610, 1514, 1456, 1261, 1141, 1100, 1068, 1036, 844, 754, 708; 1H NMR (400.31 MHz, CDC13): 8 8.00 - 7.94 (m, 4H), 7.63 - 7.58 (m, 1H), 7.48 - 7.39 (m, 5H), 7.37 - 7.32 (m, 2H), 7.16 - 7.10 (m, 5H), 6.92 - 6.88 (m, 2H), 5.82 (dddd, J = 16.7, 10.4, 6.2, 5.3 Hz, 1H), 5.40 (t, J= 8.2 Hz, 1H), 5.21 (dq, J= 17.3, 1.6 Hz, 1H), 5.16 - 5.08 (m, 2H), 4.85 - 4.80 (m, 2H), 4.67 - 4.62 (m, 3H), 4.45 (dd, J= 12.2, 2.1 Hz, 1H), 4.39 (dd, J= 12.1, 4.1 Hz, 1H), 4.12 (t, J = 8.3 Hz, 1H), 4.07 (ddt, J = 12.9, 5.3, 1.5 Hz, 1H), 3.96 - 3.90 (m, 3H), 3.86 (d, J= 8.6 Hz, 1H), 3.81 (s, 3H), 3.76 - 3.71 (m, 1H), 3.67 - 3.62 (m, 4H), 3.34 - 3.27 (m, 1H), 0.82 (s, 9H), -0.04 (s, 6H); 13C NMR (100.67 MHz, CDC13): 8 168.4, 166.1, 165.0, 159.3, 137.7, 133.5, 133.5, 133.1, 130.6, 130.3, 130.3, 129.8, 129.8, 129.7, 129.7, 129.2,

128.7(4C), 128.2, 128.2, 127.5(3C), 118.4, 113.9, 113.9, 101.2, 96.6, 82.6, 78.2, 77.8, 77.3, 75.5, 75.0, 74.2, 72.3, 69.1, 68.8, 63.0, 62.6, 55.4, 52.5, 25.8(3C), 18.0, -3.9, -5.1; HRMS (ESI-MS): m/z calcd for C51H61N3O14Si[M+Na]+: 990.3820, Found: 990.3820. [00166] Example 40: Preparation of Compound EF2

[00167] To a solution of compound EFl (2.8 g, xxx mmol) in anhydrous pyridine (20 mL) was added dropwise 20 mL of the 70% HF»py solution at 0 °C and the reaction mixture was allowed to stir at 25 °C for 5 h. After completion, ice-cold water (200 ml) was added and extracted with EtOAc (2 x 100 mL). The organic layer was washed with aqueous 1A HC1 (250 mL), saturated aq. NaHCO3 (250 mL) and brine solution (500 mL), dried over anhydrous Na2SO4, concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 35% ethyl acetate in //-hexane as mobile phase to furnish the corresponding disaccharide acceptor EF2 (2.2 g, 86%) as a thick syrup, mp 133.9 °C; [a]25D (CHC13, cl.0): +97.4°; IR (cm-1, CHC13): 3515, 3025, 2921, 2854, 2108, 1727, 1608, 1513, 1452, 1259, 1032, 826, 751, 705; 1H NMR (400.31 MHz, CDC13): 8 8.05 - 8.01 (m, 2H), 7.95 - 7.91 (m, 2H), 7.58 (ddt, J= 8.7, 7.1, 1.3 Hz, 1H), 7.48 - 7.41 (m, 3H), 7.40 - 7.33 (m, 4H), 7.16 - 7.12 (m, 5H), 6.90 - 6.86 (m, 2H), 5.83 (dddd, J= 17.2, 10.4, 6.2, 5.3 Hz, 1H), 5.33 (dd, J = 9.5, 8.0 Hz, 1H), 5.23 (dq, J = 17.2, 1.6 Hz, 1H), 5.15 (dq, J = 10.4, 1.3 Hz, 1H), 5.06 (d, J= 10.5 Hz, 1H), 4.85 (d, J= 3.6 Hz, 1H), 4.78 - 4.66 (m, 4H), 4.46 - 4.38 (m, 2H), 4.12 - 4.01 (m, 2H), 3.99 - 3.91 (m, 3H), 3.81 - 3.77 (m, 4H), 3.73 (d, J= 9.8 Hz, 1H), 3.68 - 3.63 (m, 4H), 3.33 (ddd, J= 8.8, 3.7, 1.2 Hz, 1H), 2.99 (d, J= 2.8 Hz, 1H); 13C NMR (100.67 MHz, CDC13): 8 169.2, 166.1, 165.0, 159.3, 137.8, 133.5, 133.5, 133.1, 130.7, 129.9, 129.9, 129.7(4C), 129.2, 128.7, 128.7, 128.6, 128.6, 128.5, 128.5, 128.1, 128.1, 127.9, 118.4, 113.8, 113.8, 101.4, 96.6, 81.1, 78.2, 77.9, 75.1, 74.8, 74.5, 73.3, 72.2, 69.0, 68.8, 63.0, 62.6, 55.4, 52.9; HRMS (ESI-MS): m/z calcd for C45H47N3O14 [M+Na]+: 876.2956, Found: 876.2934.

[00168] Example 41: Preparation of Compound DEFI

[00169] To a solution of glycosyl donor D4 (1.7 g, 2.2 mmol) and acceptor EF2 (1.5 g, 0.8 eq) in anhydrous CH2C12 (10 mL) was added freshly activated 4A MS powder (1.2 g/mmol) at 25 °C under argon atmosphere, the reaction mixture was stirred vigorously at -45 °C for 30 min. Then chloro[tris(2,4-di-tertbutylphenyl) phosphite] gold(I) and AgOTf (15mol% each) were added simultaneously and the mixture stirred at -40 °C for Ih. After completion, the reaction was quenched by adding Et3N and filtered through a bed of Celite®, the filtrate was concentrated in vacuo and crude residue was purified by silica gel column chromatography using 15% ethyl acetate in hexane as a mobile phase to afford the glycosylated trisaccharide DEFI (2.3 g, 90%) selectively as a- isomer. Thick syrup; [a]25D (CHC13, cl.0): +64.9°; IR (cm-1, CHC13): 3031, 2931, 2863, 2107, 1731, 1609, 1512, 1456, 1261, 1069, 1033, 749, 703; IH NMR (400.31 MHz, CDC13): 8 8.09 (dd, J = 8.3, 1.3 Hz, 2H), 7.95 (dd, J= 8.4, 1.3 Hz, 2H), 7.69 - 7.63 (m, 4H), 7.58 - 7.53 (m, IH), 7.51 - 7.46 (m, IH), 7.45 - 7.30 (m, 21H), 7.22 - 7.17 (m, 6H), 6.85 - 6.80 (m, 2H), 5.83 (dddd, J = 16.6,

10.4, 6.2, 5.3 Hz, IH), 5.46 (dd, J = 8.8, 7.9 Hz, IH), 5.40 (d, J= d Hz, IH), 5.23 (dq, J = 17.2, 1.5 Hz, IH), 5.15 (dq, J = 10.4, 1.2 Hz, IH), 5.04 (d, J = 10.3 Hz, IH), 4.91 - 4.80 (m, 6H), 4.77 (d, J= 11.1 Hz, IH), 4.70 (d, J= 10.4 Hz, IH), 4.62 (d, J= 10.3 Hz, IH), 4.45 (qd, J= 12.2, 3.0 Hz, 2H), 4.26 - 4.21 (m, IH), 4.08 (ddt, J= 12.9, 5.3, 1.4 Hz, IH), 3.97 (dd, J =

3.4, 2.0 Hz, IH), 3.96 - 3.89 (m, 5H), 3.89 - 3.83 (m, 3H), 3.78 - 3.74 (m, IH), 3.73 (s, 3H), 3.42 - 3.36 (m, 4H), 3.30 (ddd, J= 10.0, 8.0, 3.7 Hz, 2H), 1.05 (s, 9H); 13C NMR (100.67 MHz, CDC13): 8 167.9, 166.1, 165.0, 159.3, 138.4, 137.9, 137.4, 136.0, 136.0, 135.7, 135.7, 133.7, 133.7, 133.5, 133.1, 133.0, 130.4, 130.2, 130.2,

[00170] 129.9(3C), 129.8, 129.7, 129.7, 129.6, 129.1, 128.8, 128.8, 128.7, 128.7, 128.6, 128.6, 128.5(4C), 128.3, 128.3, 128.1, 127.9, 127.8(5C), 127.7, 127.7, 127.5, 127.5, 118.4, 113.9, 113.9, 101.2, 97.7, 96.6, 82.4, 80.1, 78.3, 77.8, 77.8, 75.7, 75.4, 75.1, 75.1, 74.8, 74.6, 73.8, 72.6, 69.1, 68.8, 63.6, 63.0, 62.5, 61.9, 55.3, 52.6, 27.0(3C), 19.5; HRMS (ESI-MS): m/z calcd for C81H86N6O18Si[M+Na]+: 1481.5666, Found: 1481.5657.

[00171] Example 42: Preparation of Compound DEF2

[00172] This compound was prepared from DEFI following the above described procedure for the preparation of D3. Eluent for purification: 25% ethyl acetate in //-hexane; Thick syrup; yield 1.7 g (87%) from 2.0 g; [a]25D (CH2C12, c0.5): +39.2°; IR (cm-1, CHC13): 3030, 2926, 2860, 2108, 1734, 1609, 1512, 1457, 1261, 1069, 1033, 748, 702; 1H NMR (400.31 MHz, CDC13): 5 8.11 - 8.04 (m, 4H), 7.99 - 7.92 (m, 4H), 7.65 (ddt, J= 13.1, 6.8, 1.5 Hz, 8H), 7.57 - 7.53 (m, 2H), 7.45 - 7.29 (m, 43H), 7.22 - 7.16 (m, 13H), 6.83 (dd, J = 8.6, 6.5 Hz, 4H), 5.49 - 5.38 (m, 4H), 5.18 (t, J= 3.5 Hz, 1H), 4.99 (dd, J= 36.4, 10.3 Hz, 2H), 4.89 - 4.74 (m, 12H), 4.71 - 4.61 (m, 4H), 4.52 - 4.34 (m, 5H), 4.26 - 4.18 (m, 2H), 3.98 - 3.91 (m, 8H), 3.90 - 3.81 (m, 9H), 3.73 (d, J= 4.2 Hz, 6H), 3.43 - 3.26 (m, 14H), 2.86 (s, 1H), 1.04 (s, 18H); 13C NMR (100.67 MHz, CDC13): 8 167.8, 166.2, 165.1, 159.3, 138.3,

137.8, 137.4, 136.0, 136.0, 135.7, 135.7, 133.7, 133.7, 133.5, 133.0, 130.3, 130.3, 130.2,

129.9, 129.8 (3C), 129.7, 129.7, 129.6, 129.0, 128.8, 128.7, 128.6 (3C), 128.5 (5C), 128.3 (3C), 128.1, 127.9, 127.8 (4C), 127.7, 127.7, 127.5, 127.5, 113.9, 113.9, 101.1, 97.7, 91.8, 82.4, 80.1, 77.9, 77.8, 77.4, 75.7, 75.5, 75.0, 75.0, 74.8, 74.6, 73.8, 72.5, 69.0, 63.6, 63.5, 62.3, 61.8, 55.3, 52.6, 27.0 (3C), 19.5; HRMS (ESI-MS): m/z calcd for C78H82N6O18Si[M+Na]+: 1441.5353, Found: 1441.5366.

[00173] Example 43: Preparation of Compound DEF3

[00174] This compound was prepared from DEF2 following the above described procedure for the preparation of compound D4. Eluent for purification: 18% ethyl acetate in w-hexane; White solid; yield 1.65 g (88%) from 1.7 g; mp 78.7 °C; [a]25D (CH2C12, cl.0): +30.9°; IR (cm-1, CHC13): 3284, 2934, 2862, 2110, 1742, 1730, 1608, 1513, 1454, 1261, 1076, 1030, 911, 744, 702; 1H NMR (400.31 MHz, CDC13): 8 8.10 - 8.05 (m, 2H), 7.99 - 7.95 (m, 2H), 7.65 (ddt, J= 12.9, 6.7, 1.5 Hz, 4H), 7.57 - 7.53 (m, 1H), 7.52 - 7.48 (m, 1H), 7.45 - 7.36 (m, 7H), 7.36 - 7.27 (m, 14H), 7.21 - 7.16 (m, 6H), 6.86 - 6.81 (m, 2H), 5.43 (dd, J= 9.1, 7.9 Hz, 1H), 5.39 (d, J= 3.7 Hz, 1H), 5.21 - 5.17 (m, 1H), 4.98 (d, J= 10.3 Hz, 1H), 4.90 - 4.81 (m, 4H), 4.75 (d, J = 11.1 Hz, 1H), 4.72 (d, J = 7.8 Hz, 1H), 4.69 (d, J = 10.5 Hz, 1H), 4.65 (d, J= 10.4 Hz, 1H), 4.48 - 4.38 (m, 2H), 4.20 (dd, J= 9.3, 8.5 Hz, 1H), 3.98 - 3.89 (m, 3H), 3.88 - 3.80 (m, 4H), 3.74 (s, 3H), 3.54 - 3.48 (m, 2H), 3.46 - 3.42 (m, 1H), 3.40 (s, 3H), 3.37 - 3.33 (m, 1H), 3.29 (dd, J = 9.9, 3.7 Hz, 1H), 2.57 (s, 1H), 2.16 - 2.06 (m, 2H), 1.89 - 1.77 (m, 2H), 1.67 - 1.63 (m, 1H), 1.58 - 1.46 (m, 4H), 1.33 - 1.27 (m, 1H), 1.04 (s, 9H); 13C NMR (100.67 MHz, CDC13): 8 167.8, 166.0, 165.0, 159.5, 150.8, 138.4, 137.9, 137.4, 136.0, 136.0, 135.7, 135.7, 133.8, 133.7, 133.5, 133.0, 130.5, 130.5, 129.9(7C), 129.8, 129.5, 128.9, 128.9, 128.7(4C), 128.6, 128.6, 128.5, 128.5, 128.4, 128.4,

128.1, 127.9, 127.8(7C), 127.5, 127.5, 113.9, 113.9, 101.0, 97.7, 95.5, 82.4, 82.3, 80.7, 80.1,

79.1, 77.8, 77.1, 75.7, 75.7, 75.6, 75.1, 75.0, 74.7, 74.7, 73.8, 73.7, 72.6, 64.3, 63.6, 62.2, 61.9, 55.3, 52.7, 36.8, 36.7, 27.0(3C), 25.0, 22.6, 22.6, 19.5; HRMS (ESI-MS): m/z calcd for C87H92N6O20Si[M+Na]+: 1591.6033, Found: 1591.6047.

[00175] Example 44: Preparation of Compound GH1

[00176] To a solution of glycosyl donor G13 (256 mg, 0.423 mmol) and acceptor H3 (120 mg, 0.318 mmol) in anhydrous CH2C12 (1.0 mL) was added freshly activated 4A MS powder at 25 °C under argon atmosphere. After 15 min of vigorous stirring at 25 °C, chloro[tris(2,4- di-t-butyl phenyl)phosphite]gold(I) (8mol%) and AgOTf (8mol%) were added simultaneously to the reaction mixture and stirred for 15 min. After completion, the reaction mixture was quenched with Et3N and filtered through a bed of Celite®, the filtrate was concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 20% ethyl acetate and hexane as a mobile phase to afford 230 mg (89%) of the glycosylated compound GH1. thick syrup; [a]25D (CHC13, cl.0): +17.0°; IR (cm-1, CHC13): 2955, 2860, 2109, 1742, 1460, 1371, 1237, 1091, 1040, 837, 7O1;1H NMR (400.31 MHz, CDC13): 8 7.39 - 7.36 (m, 2H), 7.35 - 7.27 (m, 7H), 7.27 - 7.24 (m, 1H), 5.94 (dddd, J= 16.6, 10.4, 6.1, 5.3 Hz, 1H), 5.35 (dq, J= 17.2, 1.5 Hz, 1H), 5.30 (d, J = 5.0 Hz, 1H), 5.25 (dq, J= 10.4, 1.2 Hz, 1H), 4.94 (d, J= 10.4 Hz, 1H), 4.92 (d, J= 3.7 Hz, 1H), 4.89 (t, J= 4.7 Hz, 1H), 4.76 - 4.70 (m, 2H), 4.67 (d, J= 11.8 Hz, 1H), 4.59 (d, J = 4.5 Hz, 1H), 4.43 (dd, J= 12.1, 2.0 Hz, 1H), 4.22 - 4.16 (m, 2H), 4.04 (ddt, 1H), 4.01 - 3.98 (m, 1H), 3.97 - 3.85 (m, 3H), 3.67 - 3.63 (m, 1H), 3.56 (s, 3H), 3.40 (dd, J= 9.8, 3.7 Hz, 1H), 2.12 (s, 3H), 2.00 (s, 3H), 0.83 (s, 9H), -0.04 (s, 3H), -0.09 (s, 3H); 13C NMR (100.67 MHz, CDC13): 8 170.8, 170.2, 170.1, 138.2, 137.9, 133.3, 128.6, 128.6, 128.3, 128.3, 128.2, 128.2, 128.0 (3C),

127.6, 118.4, 98.0, 96.7, 78.3, 77.2, 76.3, 75.0, 73.3, 72.4, 70.9, 69.4, 69.3, 68.8, 63.2, 62.2, 51.8, 25.7 (3C), 21.1, 21.0, 17.9, -4.6, -5.3; HRMS (ESI-MS): m/z calcd for C40H55N3O13Si[M+Na]+: 836.3402, Found: 836.3409

[00177] Example 45: Preparation of Compound GH2 [00178] To a solution of the compound GH1 (230 mg, 0.283 mmol) in anhydrous pyridine (2 mL) was added dropwise 2 mL of the 70% HF»py solution at 0 °C and the reaction mixture was allowed to stir at 25 °C for 5 h. After completion, ice-cold water (20 ml) was added and extracted with EtOAc (2 x 10 mL). The organic layer was washed with aqueous 1A HC1 (25 mL), saturated aq. NaHCO3 (25 mL) and brine solution (50 mL), dried over anhydrous Na2SO4, concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 60% ethyl acetate in //-hexane as mobile phase to furnish the corresponding disaccharide acceptor GH2 (170 mg, 86%) as a thick syrup; [a]25D (CHC13, cl.2): +13.0°; IR (cm-1, CHC13) : 3446, 3024, 2956, 2925, 2109, 1739, 1451, 1371, 1225, 1093, 1035, 752, 7OO;1H NMR (400.31 MHz, CDC13): 8 7.43 - 7.38 (m, 4H), 7.38 - 7.34 (m, 1H), 7.33 - 7.30 (m, 4H), 7.28 - 7.23 (m, 1H), 5.98 (dddd, J = 16.6, 10.4, 6.1, 5.4 Hz, 1H), 5.39 (dq, J= 17.2, 1.5 Hz, 1H), 5.30 (dq, J= 10.4, 1.2 Hz, 1H), 5.09 (s, 1H), 4.98 (d, 3.7 Hz, 1H), 4.96 (dt, J= 2.5, 1.2 Hz, 1H), 4.93 (d, J= 2.0 Hz, 1H), 4.77 (d, J= 11.3

Hz, 2H), 4.68 (t, J= 11.0 Hz, 2H), 4.44 (dd, J= 12.3, 1.1 Hz, 1H), 4.28 - 4.21 (m, 2H), 4.09 (ddt, J = 12.9, 6.2, 1.3 Hz, 1H), 4.01 - 3.96 (m, 1H), 3.93 - 3.84 (m, 3H), 3.76 - 3.73 (m, 1H), 3.50 (s, 3H), 3.42 (dd, J= 9.7, 3.6 Hz, 1H), 2.64 (d, J= 11.3 Hz, 1H), 2.12 (s, 3H), 2.10 (s, 3H); 13C NMR (100.67 MHz, CDC13): 8 170.7, 169.6, 169.3, 137.9, 137.3, 133.2, 128.7, 128.7, 128.3 (3C), 128.2, 128.2, 127.6, 127.6, 127.5, 118.5, 98.2, 96.7, 78.7, 75.2, 74.7, 74.5, 72.5, 69.4, 68.9, 68.6, 67.8, 67.2, 63.7, 62.3, 52.2, 21.1, 21.0; HRMS (ESI-MS): m/z calcd for C34H41N3O13 [M+Na]+: 722.2537, Found: 722.2545.

[00179] Example 46: Preparation of Compound DEFGH1

[00180] To a solution of the glycosyl donor DEF3 (25 mg, 0.016 mmol) and acceptor GH2 (7.0 mg, 0.01 mmol) in anhydrous CH2C12 (0.5 mL) was added freshly activated 4A MS powder at 25 °C under argon atmosphere. The reaction mixture was stirred for 30 min, chloro[tris(2,4-di-tertbutylphenyl) phosphite] gold(I) and AgOTf (10mol% each) were added simultaneously at -10 °C and the mixture allowed to warm to 25 °C over 30 min. After completion, the reaction was quenched with Et3N and filtered through a bed of Celite®, the filtrate was concentrated in vacuo and crude residue was purified by silica gel column chromatography using 20% ethyl acetate in hexane as mobile phase to afford the glycosylated pentasaccharide DEFGH1 (18 mg, 86%) selectively as a-isomer. Thick syrup; [a]25D (CHC13, c0.9): +102.9°; IR (cm-1, CHC13): 2956, 2926, 2862, 2108, 1737, 1456, 1369, 1256, 1146, 1105, 1071, 1035, 745, 706; 1H NMR (600.40 MHz, CDC13): 8 8.08 (d, J = 7.7 Hz, 2H), 7.99 (d, J= 7.7 Hz, 2H), 7.65 (dd, J= 19.8, 7.0 Hz, 5H), 7.53 (t, J= 7.4 Hz, 2H), 7.46 - 7.39 (m, 6H), 7.38 - 7.35 (m, 4H), 7.34 - 7.30 (m, 11H), 7.29 - 7.27 (m, 4H), 7.25 - 7.24 (m, 1H), 7.22 - 7.17 (m, 8H), 7.15 (dd, J= 9.3, 7.2 Hz, 2H), 6.81 (d, J= 8.6 Hz, 2H), 5.93 (ddt, J = 16.6, 11.0, 5.7 Hz, 1H), 5.43 (t, J= 8.5 Hz, 1H), 5.39 (d, J = 3.7 Hz, 1H), 5.37 - 5.33 (m, 1H), 5.27 (d, J = 10.3 Hz, 1H), 5.19 (d, J = 4.0 Hz, 1H), 5.03 (d, J= 10.3 Hz, 1H), 4.93 (d, J = .1 Hz, 1H), 4.90 - 4.85 (m, 4H), 4.84 - 4.80 (m, 2H), 4.78 - 4.73 (m, 3H), 4.69 - 4.64 (m, 4H), 4.53 (d, J = 10.4 Hz, 1H), 4.49 (d, J = 4.2 Hz, 1H), 4.46 (d, J = 12.2 Hz, 1H), 4.40 - 4.34 (m, 2H), 4.24 - 4.15 (m, 3H), 4.04 (dd, J = 12.9, 6.3 Hz, 1H), 3.96 - 3.86 (m, 6H), 3.86 - 3.81 (m, 6H), 3.73 - 3.69 (m, 4H), 3.66 (dd, J = 10.3, 8.6 Hz, 1H), 3.41 - 3.34 (m, 5H), 3.32 (dd, J = 10.0, 3.7 Hz, 1H), 3.25 (s, 3H), 3.21 (dd, J = 10.3, 3.6 Hz, 1H), 2.12 (s, 3H), 2.04 (s, 3H), 1.03 (s, 9H); 13C NMR (150.99 MHz, CDC13): 8 170.9, 170.2, 169.3, 167.7, 166.0, 164.8, 159.3, 138.3, 137.9, 137.7, 137.4, 137.3, 136.0, 136.0, 135.7, 135.7, 133.9, 133.6, 133.6, 133.1, 132.9, 130.2, 130.2, 130.1, 129.9, 129.9, 129.8, 129.8, 129.7, 129.7, 129.5, 129.0, 129.0, 128.9, 128.8, 128.8, 128.7, 128.7, 128.6 (4C), 128.5, 128.5, 128.4, 128.4,

128.3, 128.3, 128.2, 128.1, 127.9 (3C), 127.8 (7C), 127.7, 127.7, 127.6, 127.5, 127.5, 118.5, 113.8, 113.8, 100.8, 97.9, 97.8, 97.1, 96.6, 82.5, 80.2, 78.4, 77.7, 77.4, 77.2, 75.9, 75.8, 75.5, 75.0, 75.0, 74.9, 74.9, 74.8, 73.8, 73.6, 73.6, 72.6, 72.5, 69.6, 69.5, 69.3, 69.2, 68.8, 63.6,

63.3, 62.6, 62.2, 62.0, 61.8, 55.3, 52.7, 51.8, 27.0 (3C), 21.0, 20.9, 19.5; HRMS (ESI-MS): m/z calcd for Cl 12H121N9O30Si[M+Na]+: 2122.7886, Found: 2122.7530.

[00181] Example 47: Preparation of Compound DEFG1 [00182] To a solution of glycosyl donor DEF3 (340 mg, 0.217 mmol) and acceptor G10 (61 mg, 0.18 mmol) in anhydrous CH2C12 (2.0 mL) was added freshly activated 4A MS powder at 25 °C under argon atmosphere. After vigorous stirring for 30 min, chloro[tris(2,4- di-tertbutylphenyl)phosphite]gold(I) and AgOTf (8mol% each) were added simultaneously and the reaction mixture was stirred for 15 min, the reaction was quenched with Et3N and filtered through a bed of Celite®,the filtrate was concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 18% ethyl acetate in hexane as mobile phase to afford the glycosylated tetrasaccharide DEFG1 (286 mg, 91%) selectively as a-isomer. White solid; mp 88.1 °C; [a]25D (CHC13, cl.0): +49.0°; IR (cm-1, CHC13): 3025, 2932, 2109, 1732, 1513, 1456, 1369, 1265, 1216, 1138, 1071, 1036, 750, 7O7;1H NMR (400.31 MHz, CDC13): 5 8.11 - 8.06 (m, 2H), 8.03 - 7.99 (m, 2H), 7.69 - 7.63 (m, 4H), 7.57 - 7.50 (m, 2H), 7.46 - 7.41 (m, 4H), 7.39 - 7.36 (m, 5H), 7.35 - 7.30 (m, 13H), 7.29 - 7.28 (m, 2H), 7.23 - 7.15 (m, 8H), 6.82 (d, J = 8.6 Hz, 2H), 5.47 - 5.41 (m, 1H), 5.40 (d, J = 3.6 Hz, 1H), 5.26 (d, J= 2.3 Hz, 1H), 5.02 (d, J= 10.3 Hz, 1H), 4.90 (d, J= 10.9 Hz, 1H), 4.86 - 4.81 (m, 3H), 4.80 - 4.75 (m, 3H), 4.67 (d, J= 10.4 Hz, 1H), 4.62 - 4.55 (m, 4H), 4.39 (dd, J = 12.4, 3.1 Hz, 1H), 4.34 (d, J = 1.4 Hz, 1H), 4.22 (t, J= 8.9 Hz, 1H), 4.13 - 4.09 (m, 1H), 3.99 - 3.94 (m, 3H), 3.94 - 3.89 (m, 3H), 3.88 - 3.83 (m, 3H), 3.82 - 3.76 (m, 2H), 3.72 (s, 3H), 3.54 (s, 3H), 3.39 (s, 3H), 3.38 - 3.29 (m, 3H), 1.43 (s, 3H), 1.36 (s, 3H), 1.05 (s, 9H); 13C NMR (100.67 MHz, CDC13): 8 169.0, 167.7, 166.0, 164.8, 159.3, 138.4, 137.8, 137.4,

137.1, 136.0, 136.0, 135.7, 135.7, 133.7, 133.7, 133.5, 133.0, 130.4, 130.4, 130.3, 129.9 (3C), 129.8, 129.7 (3C), 129.1, 128.9, 128.9, 128.7 (4C), 128.6, 128.6, 128.5 (4C), 128.5, 128.3 (3C), 128.1, 127.9, 127.9, 127.8 (6C), 127.7, 127.7, 127.5, 127.5, 113.8, 113.8, 112.3, 100.8, 97.7, 97.6, 96.9, 82.6, 80.2, 77.8, 77.3, 77.2, 75.7, 75.4, 75.4, 75.1, 75.0, 74.9, 74.7, 73.6,

73.1, 72.8, 72.6, 72.5, 71.3, 69.9, 63.6, 63.3, 62.2, 61.8, 55.3, 52.6, 52.4, 27.9, 27.0 (3C), 26.3, 19.5; HRMS (ESI-MS): m/z calcd for C95H102N6O24Si[M+Na]+: 1761.6612, Found: 1761.6615

[00183] Example 48: Preparation of Compound DEFG2 [00184] To the compound DEFG1 (275 mg, 0.158 mmol) in a 25 mL flask was added 75% aq. dichloroacetic acid (5 mL) at 0 °C and the solution was stirred for 1 h. The reaction mixture was diluted with ice-cold water (25 mL), neutralized by portion-wise addition of the solid NaHCO3 and extracted with CH2C12 (3 x 15 mL). The combined organic phases were washed with brine solution, dried over anhydrous Na2SO4 and concentrated in vacuo, the crude residue was further purified by column chromatography using ethyl acetate and n- hexane as mobile phase to afford 175 mg (70%) of the compound DEFG2.

[00185] Example 49: Preparation of Compound DEFG3

[00186] To a solution of DEFG2 (148 mg, 0.094 mmol) in anhydrous CH2C12 (2 mL) was added 3.0 eq of DMAP followed by the portion-wise addition of the ethynyl cyclohexyl (4-nitrophenyl) carbonate (1.2 eq) and the reaction mixture was stirred at 25 °C for 3 h. After complete consumption of the starting hemiacetal, acetic anhydride (2.0 eq) was added and the stirring continued for another 2 h. The reaction mixture was concentrated in vacuo and purified by silica gel column chromatography using 20% ethyl acetate in //-hexane as a mobile phase to obtain compound DEFG3 (120 mg, 71%) of the desired carbonate donor. Thick syrup; [a]25D (CHC13, c0.8): +77.1°; IR (cm-1, CHC13): 2954, 2924, 2829, 2109, 1747, 1457, 1371, 1269, 1222, 1142, 1074, 1037, 910, 750, 7O5;1H NMR (400.31 MHz, CDC13): 5 8.10 - 8.02 (m, 2H), 8.00 - 7.94 (m, 2H), 7.68 - 7.61 (m, 4H), 7.57 (t, J= 7.4 Hz, 1H), 7.48 - 7.27 (m, 24H), 7.22 - 7.14 (m, 7H), 5.91 (d, J= 1.7 Hz, 1H), 5.38 (d, J= 3.6 Hz, 1H), 5.35 - 5.26 (m, 2H), 5.07 (dd, J= 3.4, 1.7 Hz, 1H), 4.90 - 4.80 (m, 3H), 4.79 - 4.68 (m, 4H), 4.65 (d, J = 10.8 Hz, 2H), 4.60 (dd, J = 12.6, 2.6 Hz, 2H), 4.42 - 4.30 (m, 2H), 4.16 - 4.06 (m, 2H), 3.94 (dq, J = 6.1, 3.7 Hz, 2H), 3.90 - 3.82 (m, 5H), 3.77 (dd, J= 19.0, 9.5 Hz, 2H), 3.59 (s, 3H), 3.51 (s, 3H), 3.36 - 3.24 (m, 3H), 2.65 (s, 1H), 2.23 - 2.09 (m, 5H), 2.01 (s, 3H), 1.93 - 1.83 (m, 2H), 1.75 - 1.63 (m, 3H), 1.58 - 1.49 (m, 2H), 1.39 - 1.31 (m, 1H), 1.04 (s, 9H); 13C NMR (100.67 MHz, CDC13): 8 171.1, 169.6, 168.1, 168.0, 165.9, 164.6, 151.0, 138.4, 137.8, 137.4, 136.9, 136.0, 136.0, 135.7, 135.7, 133.7, 133.6, 133.5, 132.9, 129.9 (3C), 129.8, 129.7 (3C), 129.0, 128.8, 128.8, 128.7, 128.7, 128.6 (4C), 128.5 (4C), 128.3 (3C), 128.1 (3C), 127.9, 127.8 (7C), 127.5, 127.5, 101.2, 98.0, 97.7, 93.3, 82.6, 82.5, 80.1, 78.8, 77.8, 75.8, 75.7, 75.4, 75.1, 75.0, 74.6, 74.4, 74.3, 74.0, 73.2, 73.2, 73.1, 72.6,

70.1, 69.6, 66.4, 63.6, 62.0, 61.9, 61.7, 52.6, 52.6, 36.8, 36.8, 27.0 (3C), 25.0, 22.7, 22.7,

20.9, 20.7, 19.5; HRMS (ESI-MS): m/z calcd for C97H104N6O27Si[M+Na]+: 1835.6616, Found: 1835.6498

[00187] Example 50: Preparation of Compound DEFGH2

[00188] This compound was prepared by the glycosylation of donor DEFG3 and acceptor H3 following the above mentioned procedure for the compound GH1. Eluent for purification: 20% ethyl acetate in w-hexane; Thick syrup; yield 20 mg (75%) from 5 mg; [a]25D (CHC13, c0.3): +206.7°; IR (cm-1, CHC13): 2957, 2925, 2863, 2109, 1742, 1457, 1371, 1264, 1225, 1145, 1073, 1036, 744, 705; 1H NMR (399.78 MHz, CDC13) 6 8.05 (d, J= 13 Hz, 2H), 7.95 (d, J= 13 Hz, 2H), 7.67 - 7.61 (m, 4H), 7.55 (t, J= 1A Hz, 1H), 7.49 - 7.42 (m, 3H), 7.41 - 131 (m, 4H), 131 - 7.26 (m, 18H), 7.25 - 7.24 (m, 1H), 7.21 - 7.12 (m, 10H), 5.93 (ddt, J = 16.5, 10.8, 5.7 Hz, 1H), 5.39 - 5.24 (m, 6H), 4.95 (dd, J = 18.9, 3.4 Hz, 2H), 4.90 - 4.82 (m, 4H), 4.81 - 4.74 (m, 3H), 4.71 (d, J = 16.0 Hz, 1H), 4.68 - 4.61 (m, 4H), 4.44 (d, J= 4.4 Hz, 1H), 4.41 - 4.30 (m, 3H), 4.23 - 4.16 (m, 2H), 4.11 (t, J = 9.0 Hz, 1H), 4.04 (dd, J = 12.9, 6.1 Hz, 1H), 3.97 - 3.82 (m, 12H), 3.78 (d, J= 9.4 Hz, 1H), 3.54 (s, 3H), 3.50 (s, 3H), 3.39 - 3.31 (m, 2H), 3.28 (dd, J = 9.8, 3.6 Hz, 1H), 3.13 (dd, J= 10.8, 3.2 Hz, 1H), 2.12 (s, 3H), 2.06 (s, 3H), 2.02 (s, 3H), 1.04 (s, 9H); 13C NMR (150.97 MHz, CDC13): 8 171.0, 170.3, 169.8, 169.6, 168.0, 165.9, 164.6, 138.3, 138.0, 137.8, 137.5, 137.3, 136.0, 136.0, 135.7, 135.7, 133.8, 133.6, 133.6, 133.2, 132.9, 129.9, 129.8 (3C), 129.7, 129.7, 129.6, 128.9 (3C), 128.7 (4C), 128.6 (4C), 128.5, 128.5, 128.4, 128.4, 128.3, 128.3, 128.2,

128.1, 127.9 (5C), 127.8 (7C), 127.6 (3C), 118.5, 101.2, 98.0, 97.8, 97.7, 96.6, 82.5, 80.1, 78.4, 77.7, 76.2, 75.8, 75.8, 75.2, 75.1, 75.0, 74.9, 74.5, 74.3, 73.8, 73.3, 73.2, 72.6, 70.0,

69.8, 69.5, 69.5, 69.3, 68.8, 63.5, 63.3, 62.1, 61.8, 61.8, 61.1, 52.7, 52.4, 27.0 (3C), 21.0,

20.9, 20.8, 19.5; HRMS (ESI-MS): m/z calcd for C106H115N9O30Si[M+Na]+: 2044.7417, Found: 2044.7214. [00189] Example 51: Preparation of Compound DEFGH3

[00190] To a biphasic solution of the pentasaccharide DEFGH1 (15 mg, 0.007 mmol) in 10: 1 CH2C12:H2O (1 mL) was added DDQ (2.5 eq) at 25 °C and stirred for 30 min. After complete consumption of the strating material, the reaction mixture was filtered through a bed of Celite®, washed with CH2C12. The filtrate was sequentially washed with saturated aq. Na2S2O3 and brine solution. Organic layer was dried over anhydrous Na2SO4 and concentrated in vacuo. The crude residue was purified by silica gel column chromatography using 25% ethyl acetate in //-hexane as mobile phase to obtain 12 mg (85%) of the compound DEFGH3. Thick syrup; [a]25D (CHC13, c0.3): +69.0°; IR (cm-1, CHC13): 2919, 2851, 2110, 1736, 1458, 1376, 1216, 1109, 1031, 757, 707; 1H NMR (600.40 MHz, CDC13): 8 8.03 (d, J = 13 Hz, 2H), 7.95 (d, J = 7.2 Hz, 2H), 7.63 (dd, J = 15.0, 6.8 Hz, 4H), 7.56 (t, J= 1A Hz, 1H), 7.52 (t, J = 1A Hz, 1H), 7.43 (d, J = 7.8 Hz, 2H), 7.42 - 7.38 (m, 5H), 7.36 - 7.28 (m, 17H), 7.24 (s, 1H), 7.22 - 7.15 (m, 9H), 7.09 (t, J= 6.8 Hz, 1H), 5.93 (ddt, J= 16.6, 11.3, 5.9 Hz, 1H), 5.39 - 5.33 (m, 3H), 5.28 - 5.25 (m, 1H), 5.20 (d, J= 3.6 Hz, 1H), 4.93 (d, J = 3.6

Hz, 1H), 4.88 - 4.84 (m, 4H), 4.79 (dd, J= 10.4, 4.1 Hz, 2H), 4.75 - 4.72 (m, 3H), 4.67 (d, J

= 10.4 Hz, 4H), 4.55 (d, J= 3.7 Hz, 1H), 4.38 (d, J= 11.7 Hz, 1H), 4.24 (dd, J= 12.3, 2.9 Hz, 1H), 4.22 - 4.17 (m, 4H), 4.10 (d, J = 8.9 Hz, 1H), 4.05 - 4.02 (m, 2H), 3.97 (t, J = 8.4

Hz, 1H), 3.95 - 3.92 (m, 1H), 3.92 - 3.89 (m, 2H), 3.88 - 3.85 (m, 5H), 3.83 (d, J = 7.9 Hz,

1H), 3.80 - 3.76 (m, 2H), 3.55 (s, 3H), 3.54 - 3.50 (m, 1H), 3.43 - 3.38 (m, 5H), 3.32 (dt, J=

6.4, 3.5 Hz, 1H), 3.10 (dd, J= 10.4, 3.4 Hz, 1H), 2.12 (s, 3H), 2.06 (s, 3H), 1.03 (s, 9H); 13C NMR (150.97 MHz, CDC13): 8 171.0, 170.3, 169.3, 167.8, 165.9, 164.9, 138.1, 137.8, 137.6,

137.4, 137.1, 136.0, 136.0, 135.7, 135.7, 134.0, 133.5, 133.4, 133.1, 132.8, 129.9(4C), 129.7, 129.7, 129.6, 129.5, 128.9, 128.9, 128.7(4C), 128.6(6C), 128.4(2C), 128.2(3C), 128.1, 128.0(5C), 127.9(3C), 127.8(4C), 127.6(2C), 127.5, 118.6, 101.2, 98.0, 97.6, 97.3, 96.5, 81.8, 81.1, 80.0, 78.4, 77.7, 75.8, 75.8, 75.1, 74.8, 74.6, 74.4, 73.8, 73.5, 73.5, 72.9, 72.8, 72.7, 69.6, 69.4, 69.2, 68.9, 68.8, 68.5, 63.4, 63.3, 62.2, 62.0, 61.8, 61.8, 53.2, 52.2, 27.0(3C), 21.0, 20.8, 19.4; HRMS (ESI-MS): m/z calcd for C104H113N9O29Si[M+Na]+: 2002.7311, Found: 2002.7004. [00191] Example 52: Preparation of Compound DEFGH4

[00192] To a solution of compound DEFGH1 (15 mg) in 4: 1 anhydrous pyridine-THF (0.5 mL) was added 0.1 mL of 70% HF»py solution at 0 °C and the reaction mixture was stirred at 25 °C for 5 h. Reaction mixture was diluted with ice-cold water (10 mL) and extracted with EtOAc (2 x 10 mL), the organic layer was washed with aqueous 17V HC1 (10 mL), saturated aq. NaHCO3 (10 mL), brine solution (10 mL), dried over anhydrous Na2SO4, concentrated in vacuo and the crude residue was purified by silica gel column chromatography using 40% ethyl acetate in w-hexane as mobile phase to afford 11 mg (85%) of compound DEFGH4 as a thick syrup. [a]25D (CHC13, c0.3): +63.3°; IR (cm-1, CHC13): 3020, 2922, 2109, 1735, 1470, 1412, 1380, 1214, 1100, 1028, 747, 668;1H NMR (400.31 MHz, CDC13): 8 8.08 - 8.04 (m, 2H), 8.03 - 7.98 (m, 2H), 7.58 (t, J= 7.4 Hz, 1H), 7.52 (t, J = 7.4 Hz, 1H), 7.47 - 7.40 (m, 4H), 7.38 - 7.31 (m, 9H), 7.31 - 7.26 (m, 8H), 7.25 (s, 2H), 7.22 - 7.13 (m, 6H), 7.10 (dd, J= 7.1, 2.4 Hz, 2H), 6.88 (d, J = 8.7 Hz, 2H), 5.98 - 5.88 (m, 1H), 5.43 - 5.38 (m, 2H), 5.35 (dd, J= 17.2, 1.5 Hz, 1H), 5.28 - 5.24 (m, 1H), 5.18 (d, J = 3.9 Hz, 1H), 5.03 (d, J= 10.2 Hz, 1H), 4.92 (d, J = 3.6 Hz, 1H), 4.88 - 4.74 (m, 8H), 4.69 - 4.62 (m, 5H), 4.56 (d, J= 10.3 Hz, 1H), 4.50 (d, J = 4.1 Hz, 1H), 4.48 - 4.43 (m, 1H), 4.41 -

4.34 (m, 2H), 4.29 - 4.24 (m, 1H), 4.22 - 4.16 (m, 2H), 4.04 (dd, J= 12.9, 6.2 Hz, 1H), 3.98 - 3.93 (m, 1H), 3.93 - 3.89 (m, 2H), 3.87 (d, J = 9.5 Hz, 1H), 3.85 - 3.81 (m, 4H), 3.79 (s, 3H), 3.77 - 3.70 (m, 2H), 3.70 - 3.64 (m, 2H), 3.63 (s, 3H), 3.52 (t, J = 9.4 Hz, 1H), 3.41 -

3.34 (m, 2H), 3.31 - 3.24 (m, 4H), 3.22 (dd, J= 10.3, 3.6 Hz, 1H), 2.11 (s, 3H), 2.04 (s, 3H); 13C NMR (150.99 MHz, CDC13): 8 170.8, 170.1, 169.4, 168.1, 166.1, 164.8, 159.4, 138.0, 137.9, 137.8, 137.5, 137.3, 133.9, 133.6, 133.2, 130.2(3C), 129.8, 129.8, 129.7(3C), 129.6, 129.0, 129.0, 128.8, 128.8, 128.7, 128.7, 128.6(4C), 128.5, 128.5, 128.3, 128.3, 128.2, 128.2, 128.1(3C), 128.0(4C), 127.9, 127.8(4C), 127.6, 118.5, 113.9, 113.9, 100.9, 98.0, 97.7, 97.2,

96.7, 82.5, 80.1, 78.4, 77.8, 77.3, 77.3, 76.0, 75.6, 75.5, 75.3, 75.2, 75.1, 74.9, 74.9, 73.9,

73.8, 73.6, 72.7, 72.3, 69.6, 69.6, 69.3, 69.3, 68.9, 63.5, 63.4, 62.8, 62.3, 62.1, 61.4, 55.4, 53.0, 51.9, 21.0, 20.9; HRMS (ESI-MS): m/z calcd for C96H103N9030 [M+Na]+: 1884.6709, Found: 1884.6536. [00193] Example 53: Preparation of Compound DEFGH5

[00194] This compound was prepared from DEFGH3, following the above procedure for compound DEFGH4 [yield 5 mg (81%) from 7 mg]. Eluent for purification: 45% ethyl acetate in w-hexane; Thick syrup; [a]25D (CHC13, c0.2): +48.0°; IR (cm-1, CHC13): 2922, 2109, 1733, 1456, 1376, 1216, 1027, 756; 1H NMR (600.40 MHz, CDC13): 8 8.04 (d, J= 7.8 Hz, 2H), 7.99 (d, J= 7.5 Hz, 2H), 7.59 (t, J= 13 Hz, 1H), 7.55 - 7.53 (m, 1H), 7.45 (t, J = 7.6 Hz, 2H), 7.41 (t, J= 7.5 Hz, 3H), 1 1 - 132 (m, 12H), 7.24 - 7.13 (m, 10H), 5.96 (ddt, J = 16.0, 10.6, 5.4 Hz, 1H), 5.45 (d, J= 3.2 Hz, 1H), 5.41 - 5.36 (m, 2H), 5.28 (d, J= 10.1 Hz, 1H), 5.24 - 5.19 (m, 1H), 4.96 - 4.94 (m, 1H), 4.92 - 4.88 (m, 2H), 4.87 - 4.82 (m, 4H), 4.77 (d, J = 9.4 Hz, 2H), 4.72 (d, J = 12.3 Hz, 2H), 4.71 - 4.69 (m, 2H), 4.67 (d, J= 5.8 Hz, 1H), 4.63 (d, J= 3.1 Hz, 1H), 4.40 (d, J= 12.1 Hz, 1H), 4.35 - 4.29 (m, 2H), 4.28 - 4.19 (m, 5H), 4.16 (s, 1H), 4.07 (dd, J= 12.6, 5.9 Hz, 1H), 4.01 - 3.96 (m, 3H), 3.92 - 3.90 (m, 1H), 3.89 - 3.86 (m, 4H), 3.83 (s, 3H), 3.82 - 3.80 (m, 1H), 3.79 (d, J= 9.2 Hz, 1H), 3.69 - 3.66 (m, 1H), 3.57 (t, J = 9.2 Hz, 2H), 3.47 (d, J= 10.3 Hz, 1H), 3.43 (s, 3H), 3.41 - 3.39 (m, 1H), 3.32 (dd, J = 10.1, 3.4 Hz, 1H), 3.15 (dd, J = 10.3, 2.9 Hz, 1H), 2.13 (s, 3H), 2.10 (s, 3H); 13C NMR (150.99 MHz, CDC13): 8 170.9, 170.3, 169.3, 168.5, 166.0, 164.9, 138.0, 137.9, 137.8,

137.4, 137.0, 133.9, 133.5, 133.2, 129.9(3C), 129.7, 129.7, 128.9, 128.9, 128.7(4C), 128.6(6C), 128.5, 128.2(6C), 128.1(6C), 128.0, 128.0, 127.8, 127.8, 127.5, 118.5, 101.3, 98.1, 97.5, 97.2, 96.7, 82.1, 81.5, 80.0, 78.5, 77.7, 75.8, 75.6, 75.2, 74.8, 74.7, 74.2, 74.0,

73.4, 73.4, 73.1, 72.7, 72.4, 69.8, 69.4, 69.4, 68.9, 68.9, 68.6, 63.5, 63.4, 62.3, 62.1, 62.0, 61.3, 53.5, 52.2, 21.0, 20.8; HRMS (ESI-MS): m/z calcd for C88H95N9O29 [M+Na]+: 1764.6133, Found: 1764.6050.

[00195] The foregoing examples are merely illustrative and are not to be taken as limitations upon the scope of the invention. Various changes and modifications to the disclosed embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the scope of the invention.