PROCESS FOR PREPARING N,N-DIMETHYL-4-((6-OXOPYRIMIDIN-1 (6H)-YL)METHYL)BENZAMIDE FROM 4-((6-OXOPYRIMIDIN-1 (6H)-YL)METHYL)BENZOIC ACID, AND CRYSTALLINE FORMS OF THE BENZAMIDE

The present invention relates to a process for the synthesis of N,N-dimethyl-4-((6- oxopyrimidin-1 (6H)-yl)methyl)benzamide and 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzoic acid, a process for synthesising crystalline forms of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)- yl)methyl)benzamide, and crystalline forms of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)- yl)methyl)benzamide. a1 -Antitrypsin (A1AT) is a member of the serpin superfamily produced by the liver and secreted into the blood. It inhibits a variety of serine proteases, especially neutrophil elastase. When blood levels of A1AT are low, excessive neutrophil elastase activity degrades lung tissue resulting in respiratory complications such as chronic obstructive pulmonary disease (COPD).

The reference range of A1 AT in blood is 0.9-2.3 g/L. Levels lower than this are typical of a1 - antitrypsin deficiency (A1AD or AATD), a genetic disorder caused by mutations in the SERPINA1 gene, coding for A1 AT. The Z mutation, the most common cause of AATD, is the substitution of glutamate to lysine at position 366 of A1AT (UniProtKB - P01009 (A1AT HUMAN)), corresponding to position 342 in the mature protein (Z A1AT). The Z mutation affects the folding of A1AT resulting in only a small fraction acquiring the native/active state. The remainder is either cleared as misfolded protein or accumulates in the liver as stable polymers. As a consequence of the misfolding, homozygous carriers of the Z mutation (ZZ) have plasma levels of A1AT that are 10-15% of normal, predisposing carriers to COPD. Accumulation of Z A1AT polymers in liver cells predisposes carriers to cirrhosis, liver cancer and other liver pathologies.

The current treatment for the lung manifestation of AATD involves augmentation therapy using A1AT concentrates prepared from the plasma of blood donors. The US FDA has approved the use of four A1 AT products: Prolastin, Zemaira, Glassia, and Aralast. Dosing is via once weekly intravenous infusion. Augmentation therapy has been demonstrated to slow progression of COPD. The liver manifestations of AATD (e.g. cirrhosis and cancer) are treated with steroids and liver transplantation. Investigational approaches to improved treatment of the liver manifestations include inhibition of Z A1AT polymerisation and increased clearance of polymers through the activation of autophagy. Investigational approaches to improved treatment of both the lung and the liver manifestations are directed towards improvement of Z A1 AT folding and secretion. There is a need for new compounds, and/or processes for the synthesis of compounds, which may for example be able to treat a1 -antitrypsin deficiency.

According to a first aspect of the present invention, there is provided a process for the preparation of a compound of formula IV, the process comprising: a) a step of reacting a compound of formula I with a compound of formula II in the presence of a base and a solvent to form a compound of formula (III), wherein R is methyl or tertiary butyl, and L is a leaving group; b) a step of hydrolysis of the compound of formula III in the presence of an acid, followed by the addition of a base to thereby increase the pH of the reaction mixture and precipitate the compound of formula IV.

The compound of formula IV may also be referred to as 4-((6-oxopyrimidin-1 (6H)- yl)methyl)benzoic acid. The compound of formula I may also be referred to as pyrimidin- 4(3H)-one.

L may be a halogen, or a sulphonate. The halogen may be one of chlorine, bromine, fluorine or iodine. The sulphonate may have the formula -OSO2R1, wherein Ri is an optionally substituted alkyl, for example an optionally substituted Ci- ₈ alkyl, for example Ci- ₈ alkyl. Preferably, L is bromine.

R may be tertiary butyl or methyl. Preferably, R is methyl.

Preferably, step (a) further comprises the addition of water to the reaction mixture to thereby precipitate the compound of formula III. The water may be added to the reaction mixture following the reaction between the compound of formula I and the compound of formula II.

The base of step (a) may be one or more of sodium carbonate, sodium hydroxide, sodium hydride, potassium carbonate, caesium carbonate, lithium hydroxide, potassium hydroxide or caesium hydroxide. Preferably, the base is sodium hydroxide or caesium carbonate.

The solvent of step (a) may be one or more of ethanol, isopropyl alcohol, acetone, dimethylformamide or dimethyl sulfoxide. Preferably, the solvent is dimethylformamide or dimethyl sulfoxide.

It will be appreciated that the solvent and base may be any appropriate combination of the solvents and bases set out above. For example, the solvent and base combination may be sodium carbonate and ethanol, sodium hydroxide and isopropyl alcohol, sodium carbonate and acetone, sodium hydride and dimethylformamide, sodium carbonate and dimethylformamide, potassium carbonate and dimethylformamide, caesium carbonate and dimethylformamide, sodium carbonate and dimethyl sulfoxide, potassium carbonate and dimethyl sulfoxide, caesium carbonate and dimethyl sulfoxide, lithium hydroxide and dimethyl sulfoxide, sodium hydroxide and dimethyl sulfoxide, potassium hydroxide and dimethyl sulfoxide or caesium hydroxide and dimethyl sulfoxide.

Preferably, the solvent and base combination is either caesium carbonate and dimethylformamide or sodium hydroxide and dimethyl sulfoxide. The reaction of step (a) may take place at a temperature below about 30 ^e C, for example from about 15 ^e C to about 30 ^e C, for example from about 25 ^e C to about 30 ^e C.

The process may comprise a step of filtration following the precipitation of the compound of formula III to thereby isolate the compound of formula III. The process may comprise a further step of purification of the compound of formula III, for example by column chromatography, high performance liquid chromatography, liquid chromatography or gas chromatography.

The applicant has found that in the case of the solvent and base being sodium hydroxide and dimethyl sulfoxide or sodium hydroxide and dimethyl sulfoxide, the addition of water following the reaction of the compound of formula I with the compound of formula II leads to precipitation of a compound of formula III, meaning that the compound of formula III can be isolated by filtration alone and purification by chromatography is not required.

The hydrolysis reaction of step (b) may take place in the presence of water and an acid.

The acid of step (b) may be an aqueous acid, for example one or more of aqueous hydrochloric acid, aqueous trifluoroacetic acid or aqueous sulphuric acid, for example aqueous hydrochloric acid or aqueous sulphuric acid.

The hydrolysis reaction of step (b) may include a step of in situ distillation of a methanol by product from the reaction mixture. The in situ distillation may be vacuum distillation. The distillation rate may be about 0.1 to 0.5 vol/hour. The applicant has found that such an in situ distillation step may aid full conversion of the reactants to the compound of formula IV. Alternatively, the reaction mixture may be repeatedly exposed to the reaction conditions.

The hydrolysis reaction of step (b) may take place at a temperature of from about 70 ^e C to about 80 ^e C, for example from about 75 ^e C to about 80 ^e C.

The base of step (b) may be a mixture of sodium chloride and trisodium citrate or a mixture of sodium carbonate and sodium hydroxide, or sodium hydroxide, for example aqueous sodium hydroxide. In the case of the acid of step (b) being aqueous hydrochloric acid, the base may be a mixture of sodium chloride and trisodium citrate. In the case of the acid of step (b) being aqueous sulphuric acid, the base may be sodium hydroxide, such as aqueous sodium hydroxide.

The addition of the base in step (b) may lead to the reaction mixture having a pH of about It has been found that increasing the pH of the reaction mixture following the hydrolysis leads to precipitation of the compound of formula IV as a clean filterable precipitate in high yield.

The reaction mixture of step (b) may be cooled to room temperature (for example from15 ^e C to 25 ^e C) or to 25 ^e C prior to the addition of the base.

The precipitate of compound IV may be isolated by filtration and subjected to drying.

The reaction mixture of step (b) may be at a temperature of about 40 ^e C before addition of the base. For example, the temperature of the reaction mixture may be adjusted to about 40 ^e C before addition of the base. The reaction mixture may then be allowed to cool to ambient temperature (for example from 18 ^e C to 30 ^e C, for example 19 ^e C to 21 ^e C) prior to isolation, for example by filtration. The applicant has found that the addition of the base at a temperature of about 40 ^e C followed by cooling yields a precipitate that can be more easily dried.

The process may comprise: a) a step of reacting a compound of formula I with a compound of formula II in the presence of sodium hydroxide and dimethyl sulfoxide, followed by the addition of water to the reaction mixture to thereby precipitate a compound of formula III, wherein R is methyl and L is bromine; and b) a step of hydrolysis of the compound of formula III in the presence of aqueous hydrochloric acid, followed by the addition of an aqueous mixture of trisodium citrate and sodium chloride to thereby increase the pH of the reaction mixture and precipitate the compound of formula IV, or a step of hydrolysis of the compound of formula III in the presence of aqueous sulphuric acid, followed by the addition of an aqueous solution of sodium hydroxide to thereby increase the pH of the reaction mixture and precipitate the compound of formula IV.

The process may comprise a further purification step, for example a step of purification of the compound of formula IV. The purification may be by chromatography, for example column chromatography, high performance liquid chromatography, liquid chromatography or gas chromatography. In a further aspect of the present invention, there is provided a process for the preparation of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide, the process comprising: a step of amidification of the compound of formula IV to thereby form N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide. The compound of formula IV may be prepared by the process according to any statement set out above.

The compound N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide has the following formula (V):

The amidification may comprise a step of reacting the compound of formula IV with an amide coupling agent. The amide coupling agent may be propylphosphonic anhydride, carbonyl diimidazole or another suitable amide coupling agent. Preferably, the amide coupling agent is carbonyl diimidazole. The reaction of compound IV with the coupling agent may take place in the presence of ethyl acetate. The reaction of compound IV with the coupling agent may take place at a temperature of from 55 ^e C to 60 ^e C, for example 60 ^e C.

The amidification may further comprise a step of adding dimethylamine to the reaction mixture following the step of reacting the compound of formula IV with the amide coupling agent (for example carbonyl diimidazole or propylphosphonic anhydride). The dimethylamine may be added to the reaction mixture in the presence of tetrahydrofuran. Following the addition of dimethylamine to the reaction mixture, the resulting mixture may have a temperature of about 60 ^e C.

Alternatively, the amidification step may further comprise a step of adding the combination of dimethylamine hydrochloride and a base to the reaction mixture following the step of reacting the compound of formula IV with the amide coupling agent (for example carbonyl diimidazole or propylphosphonic anhydride). The base may be trimethylamine or trimethyl amine.

The dimethylamine hydrochloride and the base (for example trimethylamine or trimethyl amine) may be added to the reaction mixture in the presence of tetrahydrofuran. Following the addition of the dimethylamine hydrochloride and the base to the reaction mixture, the resulting mixture may have a temperature of about 60 ^e C.

The process may comprise a step of adding an aqueous acid solution to the reaction mixture following the amidification. The aqueous acid solution may comprise the combination of sodium chloride and hydrochloric acid or the combination of magnesium sulphate and citric acid. Preferably, the aqueous acid solution comprises magnesium sulphate and citric acid.

Alternatively, the process may comprise the step of adding solid citric acid, such as citric acid monohydrate, followed by the addition of aqueous magnesium sulphate solution.

The applicant has found that adding magnesium sulphate and citric acid leads to the removal of excess basic reagents and by products while keeping the compound of formula V in the organic phase.

The process may further comprise a step of solvent extraction following amidification to yield the compound of formula V. The solvent used for the solvent extraction may be a combination of ethyl acetate and ethanol, for example in a ratio of 9:1 ethyl acetate to ethanol. Following separation, the extracted organic phase may be concentrated by vacuum distillation.

The process may further comprise purification steps, for example purification of the isolated compound of formula V. Purification may be by chromatography, for example column chromatography, high performance liquid chromatography, liquid chromatography or gas chromatography.

The process may comprise: a) a step of reacting a compound of formula I with a compound of formula II in the presence of sodium hydroxide and dimethyl sulfoxide, followed by the addition of water to the reaction mixture to thereby precipitate a compound of formula III, wherein R is methyl and L is bromine; b) a step of hydrolysis of the compound of formula III in the presence of aqueous hydrochloric acid, followed by the addition of an aqueous mixture of trisodium citrate and sodium chloride to thereby increase the pH of the reaction mixture and precipitate the compound of formula IV, or a step of hydrolysis of the compound of formula III in the presence of aqueous sulphuric acid, followed by the addition of an aqueous solution of sodium hydroxide to thereby increase the pH of the reaction mixture and precipitate the compound of formula IV; c) a step of amidification of the compound of formula IV comprising reacting the compound of formula IV with carbonyl diimidazole in the presence of ethyl acetate, followed by the addition of dimethylamine in the presence of tetrahydrofuran to the reaction mixture to thereby form N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide.

In a further aspect of the present invention, there is provided a compound prepared by the process according to any statement set out above.

In a further aspect of the present invention, there is provided a process for the preparation of a crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide, the process comprising recrystallizing N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)- yl)methyl)benzamide from ethanol.

The N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be prepared according to any of the statements above relating to the process for preparing N,N-dimethyl- 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide.

In a further aspect of the present invention there is provided crystalline form 1 of N,N- dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide prepared by the above process.

In a further aspect of the present invention, there is provided a process for the preparation of a crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide, the process comprising recrystallizing N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)- yl)methyl)benzamide from ethyl acetate. The ethyl acetate may be hot ethyl acetate. The N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be prepared according to any of the statements above relating to the process for preparing N,N-dimethyl- 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide.

In a further aspect of the present invention there is provided crystalline form 2 of N,N- dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide prepared by the above process.

In a further aspect of the present invention, there is provided crystalline form 1 of N,N- dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide characterised by having 5 or more peaks selected from the following X-ray diffraction peaks obtained with CUKa radiation: 5.5, 11.1 , 12.2, 16.0, 16.6, 17.4, 18.2, 19.3, 21.2, 21.4, 23.7, 24.5, 25.2, 25.4, 26.0, 26.62, 26.9, 27.5, 29.8, 32.4 and 33.7 degrees 2Q.

The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by 10 or more, for example 15 or more, for example 20 or more, for example all 21 of the following X-ray diffraction peaks obtained with CUKa radiation: 5.5, 11.1 , 12.2, 16.0, 16.6, 17.4, 18.2, 19.3, 21.2, 21.4, 23.7, 24.5, 25.2, 25.4, 26.0, 26.62, 26.9, 27.5, 29.8, 32.4 and 33.7 degrees 2Q.

The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by having 5 or more, for example 10 or more, for example 15 or more, for example 20 or more, for example all 21 of the Cu X-ray powder diffraction peaks as shown in Table 2.

The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the fractional atomic coordinates and equivalent isotropic displacement parameters as shown in Table 4.

The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the powder X-ray diffraction pattern substantially as shown in Figure 1 . The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the region of the powder X-ray diffraction pattern substantially as shown in Figure 1 having 2-theta values from 5 to 35.

The crystalline form 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6FI)-yl)methyl)benzamide may be characterised by the following parameters: crystal system = monoclinic, space group = P21 /n, A, a = 6.06802(8) A, b = 31 .6418(3) A, c = 7.09782(11 ) A, b = 113.6214(16)°. The crystalline form 1 of 1 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the parameters set out in Table 3.

In a further aspect of the present invention, there is provided a crystalline form 2 of N,N- dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide characterised by having 5 or more peaks selected from the following X-ray diffraction peaks obtained with CUKa radiation: 9.3, 12.1 , 12.2, 14.7, 15.6, 17.0, 17.6, 18.1 , 18.6, 18.7, 19.0, 19.3, 20.3, 20.8, 21.0, 22.1 , 22.6, 22.9, 24.1 , 24.4, 24.6, 25.3, 25.7, 26.2, 26.6, 27.4, 28.3, 29.5, 30.0, 30.3, 31.2, 32.6, 37.3 and 40.7 degrees 2Q.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by 10 or more, for example 15 or more, for example 20 or more, for example all 25 or more, for example 30 or more, for example all 34 of the following X-ray diffraction peaks obtained with CUKa radiation: 9.3, 12.1 , 12.2, 14.7, 15.6, 17.0, 17.6, 18.1 , 18.6, 18.7, 19.0, 19.3, 20.3, 20.8, 21.0, 22.1 , 22.6, 22.9, 24.1 , 24.4, 24.6, 25.3, 25.7, 26.2, 26.6, 27.4, 28.3, 29.5, 30.0, 30.3, 31.2, 32.6, 37.3 and 40.7 degrees 2Q.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by having 5 or more, for example 10 or more, for example 15 or more, for example 20 or more, for example 25 or more, for example 30 or more, for example all 34 of the Cu X-ray powder diffraction peaks as shown in Table 5.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the fractional atomic coordinates and equivalent isotropic displacement parameters as shown in Table 7.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the powder X-ray diffraction pattern substantially as shown in Figure 2.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide may be characterised by the region of the powder X-ray diffraction pattern substantially as shown in Figure 2 having 2-theta values from 8 to 42.

The crystalline form 2 of N,N-dimethyl-4-((6-oxopyrimidin-1 (6FI)-yl)methyl)benzamide may be characterised by the following parameters: crystal system = triclinic, space group = P-1 , A, a = 6.10847(17) A, b = 9.3268(2) A, c = 11.4631 (3) A, a = 88.5232(19)°, b =

81.396(2)°, Y= 81.211 (2)°. The crystalline form 1 of 1 of N,N-dimethyl-4-((6-oxopyrimidin-

1 (6H)-yl)methyl)benzamide may be characterised by the parameters set out in Table 6. The use of a numerical range in this description is intended unambiguously to include within the scope of the invention all individual integers within the range and all the combinations of upper and lower limit numbers within the broadest scope of the given range. As used herein, the term “comprising” is to be read as meaning both comprising and consisting of.

Unless otherwise defined, all the technical and scientific terms used here have the same meaning as that usually understood by an ordinary specialist in the field to which this invention belongs. Similarly, all the publications, patent applications, all the patents and all other references mentioned here are incorporated by way of reference in their entirety (where legally permissible).

Particular non limiting examples of the present invention will now be described with reference to the following examples and drawings, in which:

Figure 1 is a powder X-ray diffraction spectrum of crystalline form 1 of N,N-dimethyl-4-((6- oxopyrimidin-1 (6H)-yl)methyl)benzamide. X-axis shows 2-theta values;

Figure 2 is a powder X-ray diffraction spectrum of crystalline form 2 of N,N-dimethyl-4-((6- oxopyrimidin-1 (6H)-yl)methyl)benzamide. X-axis shows 2-theta values;

Figure 3 shows the solid state structure of crystalline form 1 of N,N-dimethyl-4-((6- oxopyrimidin-1 (6H)-yl)methyl)benzamide; and Figure 4 shows the solid state structure of crystalline form 2 of N,N-dimethyl-4-((6- oxopyrimidin-1 (6H)-yl)methyl)benzamide.

Examples

Example 1 : Synthetic process overview

Step (a)

Step (b1) or Step (b2)

1) HCI, water 1) H ₂ S0 ₄ , water

2) trisodium citrate 2) NaOH, water NaCI, water

Step (c) ,

Scheme 1

Scheme 1 illustrates an example process for the synthesis of the compound of formula IV (Compound 4), the compound of formula V (Compound 5) and crystalline forms 1 and 2 of the compound of formula V.

The process shown in scheme 1 comprises a process for the preparation of the compound of formula IV which comprises steps (a) and (b1) or step (b2); a process for the preparation of compound V from the compound of formula IV which comprises step (c); a process for the preparation of compound V from the compounds of formula I and II which comprises steps (a), (b) and (c); and a process for the preparation of crystalline forms 1 and 2 of the compound of formula V which comprises step (d1 ) or step (d2). Step (a)

The process shown in step (a) comprises a step of reacting the compound of formula I with the compound of formula II in the form of compound 2 as shown in scheme 1 . The reaction takes place in the presence of a base in the form of sodium hydroxide and a solvent in the form of dimethyl sulphoxide (DMSO), although it will be appreciated that other bases and solvents can be used.

It was found that the reaction of step (a) led to the formation of two ester isomers (compound 3 and 3a), as shown in scheme 2. Scheme 2

A range of bases and solvents were tested for use in the process of step (a) as illustrated in Table 1 .

As shown in Table 1 , the combination of caesium carbonate and dimethylformamide (DMF) led to a ratio of compound 3 to compound 3a of 11 :1.

While the combination of sodium hydroxide and DMSO yielded a ratio of compound 3 to compound 3a of 4.2:1 , this base and solvent is safe, scalable and cheap and provided a useful proportion of the desired ester.

The applicant found that the addition of water to the reaction mixture when the reaction of step (a) was carried out in the presence of the combination of caesium carbonate and DMF or the combination of sodium hydroxide and DMSO surprisingly led to the precipitation of compound 3 only. This means that compound 3 could be isolated by filtration, so separation by column chromatography is not necessary.

It was found that if compound 2a, the tertiary butyl analogue of compound 2, was used instead of compound 2, then the precipitate resulting from the addition of water to the reaction mixture included a mixture of isomeric alkylation products that required purification by column chromatography.

Step (b)

Step (b1) comprises the hydrolysis of compound 3 in the presence of an acid in the form of aqueous hydrochloric acid, followed by the addition of a base in the form of an aqueous solution of sodium chloride and trisodium citrate to thereby increase the pH of the reaction mixture to yield a precipitate of the compound of formula IV (compound 4). Step (b2) comprises the hydrolysis of compound 3 in the presence of an acid in the form of aqueous sulphuric acid, followed by the addition of a base in the form of an aqueous solution of sodium hydroxide to thereby increase the pH of the reaction mixture to yield a precipitate of the compound of formula IV (compound 4).

As shown in scheme 1 , the ester 3 is hydrolysed by treatment with aqueous hydrochloric acid or aqueous sulphuric acid , although it will be appreciated that other aqueous acids could be used, for example aqueous trifluoroacetic acid.

Full conversion to compound 4 is achieved by either repeated exposure to the reaction conditions or in situ distillation of the methanol by-product from the mixture during the reaction. It was found that the isolation of compound 4 requires that the acidic reaction mixture be partially basified to produce the neutral carboxylic acid 4. While sodium carbonate and sodium hydroxide could be used to achieve this increase in the pH of the reaction mixture, if aqueous hydrochloric acid is used in the reaction an aqueous solution of sodium chloride and trisodium citrate was found to be particularly effective at achieving partial neutralisation in order to yield the carboxylic acid 4 as a clean filterable precipitate in high yield. If aqueous sulphuric acid is used in the reaction, an aqueous solution of sodium hydroxide was found to be particularly effective at achieving partial neutralisation in order to yield the carboxylic acid 4 as a clean filterable precipitate in high yield. The precipitation of compound 4 may be conducted at a higher temperature (e.g. 40 °C) followed by cooling to ambient temperature with stirring before filtration, which yields a precipitate that can be dried easily before the next process step.

Step (c)

Step (c) comprises a process of amidification of compound 4. Compound 4 is first reacted with an amide coupling agent in the form of carbonyl diimidazole (CDI) in the presence of ethyl acetate followed by reaction with dimethylamine in the presence of tetrahydrofuran (THF) to form the compound of formula V (compound 5).

As shown in scheme 1 , compound 4 is reacted with CDI in the presence of ethyl acetate at an elevated temperature. The activation process enables the smooth reaction with dimethylamine in the presence of THF as shown in scheme 1. The solubility of carboxylic acid 4 in tetrahydrofuran and also in ethyl acetate is fairly low. Despite this, surprisingly, it was found that the reaction of acid 4 with CDI in ethyl acetate at elevated temperature is very efficient. Dimethylamine hydrochloride and an additional base such as trimethylamine or triethylamine can also be used instead of dimethylamine. The isolation of compound 5 was found to be challenging due to its solubility in the water and aqueous acid. Water and aqueous acid are typically used to remove basic amine reagents and by-products, such as excess dimethylamine and imidazole, from the reaction mixture. Treatment of the reaction mixture with a two molar aqueous solution of magnesium sulphate with added citric acid was found to remove basic reagents and by-products while keeping the compound 5 in the organic phase.

Step (d)

Step (d) comprises a step of recrystallizing compound 5 from either ethanol or ethyl acetate to yield crystalline form 1 and crystalline form 2 of compound 5 respectively.

Example 2: Step (a), the synthesis of compound 3.

Process 1

Methyl 4-((6-oxopyrimidin-1 (6/-/)-yl)methyl)benzoate 3.

3/-/-Pyrimidin-4-one 1 (2.11 g, 0.022 mol) was dissolved in DMF (60 ml) at 25 °C. Powdered CS ₂ CO ₃ (9.77 g, 0.030 mol) was added and the reaction was stirred for 25 minutes. Methyl 4-(bromomethyl)benzoate (4.58 g, 0.020 mol) was added while maintaining the temperature below 30 °C. The reaction was stirred at 25 °C for 20 hours, and then water (15 ml) was added. The reaction was stirred for a further 3 hours at 25 °C and the reaction was filtered. The solid was washed with water (15 ml) and then dried in vacuo to give the ester as a solid 3 (3.69 g, 91 % by NMR, inc 9% DMF w/w, corrected yield = 69%). d _H (500 MHz, CDCI ₃ ) 8.15 (1 H, s), 8.03 (2H, d, J = 8 Hz), 7.99 (1 H, d, J = 6.5 Hz), 7.38 (2H, d, J = 8 Hz), 6.50 (1 H, d, J 6.5 Hz), 5.15 (2H, s), 3.91 (3H, s).

Process 2

Methyl 4-((6-oxopyrimidin-1 (6/-/)-yl)methyl)benzoate 3.

3/-/-Pyrimidin-4-one 1 (20.8 g, 0.216 mol) was dissolved in DMSO (565 ml) at 25 °C. Powdered NaOH (8.64 g, 0.216 mol) was added and the reaction was stirred for 25 minutes. A solution of methyl 4-(bromomethyl)benzoate (44.8 g, 0.196 mol) in DMSO (110 ml) was added while maintaining the temperature below 30 °C. The reaction was stirred at 25 °C for 20 hours, and then water (175 ml) was added. The reaction was stirred for a further 3 hours at 25 °C and the reaction was filtered. The solid was washed with water (100 ml) and then dried in vacuo to give the ester as a solid 3 (24.7 g, 52 %). d _H (500 MHz, CDCI ) 8.15 (1 H, s), 8.03 (2H, d, J = 8 Hz), 7.99 (1 H, d, J = 6.5 Hz), 7.38 (2H, d, J = 8 Hz), 6.50 (1 H, d, J 6.5 Hz), 5.15 (2H, s), 3.91 (3H, s).

Process 3

Methyl 4-((6-oxopyrimidin-1 (6/-/)-yl)methyl)benzoate 3.

3/-/-Pyrimidin-4-one 1 (675.2 g) was dissolved in DMSO (16 litres) at 20 °C. Solid NaOH (284.3 g) was added and the reaction was stirred for 2 hours keeping the temperature between 15 °C and 25 °C. A solution of methyl 4-(bromomethyl)benzoate (1505 g) in DMSO (3300 ml) was added to the stirring reaction over 1 hour while maintaining the temperature below 30 °C. An additional 300 ml of DMSO was used to wash the transfer vessel and line and this was added to the reaction. The reaction was then cooled to 25 °C over 15 minutes and stirred for an addition 2 hours. Water (6580 ml) was then added to the stirring reaction over 1 hour keeping the temperature below 30 °C, and then the mixture was stirred at 25 °C for an additional 2 hours. The reaction mixture was then filtered and the solid on the filter was washed with water (1500 ml x3) and then dried on the filter under an atmosphere of nitrogen gas, to give the ester 3 (1054 g, 66 %).

Example 3: Step (b), the synthesis of compound 4 Process 1

4-((6-Oxopyrimidin-1 (6H)-yl)methyl)benzoic acid 4.

A solution of methyl 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzoate 3 (49.0 g, 0.201 mol) in 2 M HCI (200 ml_, 0.4 mol) and cone. HCI (20 ml_, 0.233 mol) was heated at 80 °C for 28 hours. The reaction mixture was cooled to room temperature and an aqueous solution of trisodium citrate and NaCI (both at 1 .2 M) was added until the pH reached ~4. The solids were filtered, washed with water and dried under vacuum to yield a pale yellow solid (39.0 g). ¹ H NMR analysis showed that this solid contained roughly 10 mol % unreacted starting material. Therefore a solution of this material (36.0 g) in 2 M HCI (156 ml_, 0.313 mol) and cone. HCI (15.6 ml_, 0.181 mol) was heated at 80 °C for 17 hours. The reaction mixture was cooled to room temperature and 2 M NaOH was added until the pH reached ~4. The solids were then filtered, washed with water and dried under vacuum to yield the acid 4 as a pale yellow solid (29.0 g). d _H (300 MHz, cfe-DMSO) 8.68 (1 H, s), 7.97-7.88 (3H, m), 7.44-7.36 (2H, m), 6.44 (1 H, dd, J = 6.5 Hz, 0.5 Hz), 5.17 (2H, s).

Process 2

4-((6-Oxopyrimidin-1 (6H)-yl)methyl)benzoic acid 4.

A mixture of methyl 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzoate 3 (1048.5 g) in 2 M HCI (4300 ml_), and then additional cone. HCI (420 ml.) was added and the mixture was heated at 75 °C over 1 hour and then heated at that temperature for 48 hours under a stream of nitrogen gas. The reaction was then cooled to 25 °C over 4 hours. To the reaction was added 7580 ml of an aqueous solution that contained sodium chloride (1 .2 M) and trisodium citrate (1 2M) resulting in a reaction mixture of pH 4. The mixture was stirred for 1 hour at 20 °C and then filtered, and the solid on the filter was washed with water (5000 ml x3) and then dried on the filter under an atmosphere of nitrogen gas, to give the acid 4 (841 g, 73.2 %).

Process 3

4-((6-Oxopyrimidin-1 (6H)-yl)methyl)benzoic acid 4.

A mixture of methyl 4-((6-oxopyrimidin-1 (6/-/)-yl)methyl)benzoate 3 (150.0 g), water (510 ml_), and cone. H ₂ S0 (105 ml.) was heated at 75 °C over 1 hour and then heated at that temperature for 14 hours under a reduced pressure of 300 to 400 mBar. During this time water was added in order to replace the distillate thus maintaining the original volume of the reaction. The reaction was then cooled to 20 °C over 4 hours. To the reaction was added an aqueous solution of sodium hydroxide (a mixture of 525 ml. of water and 111 g of sodium hydroxide) resulting in a reaction mixture of pH 2 to pH 4. The mixture was stirred for 1 hour at 20 °C and then filtered, and the solid on the filter was washed with water (450 ml. x3) and then dried on the filter under an atmosphere of nitrogen gas, to give the acid 4 (135.8 g, 96 %).

Example 4: Step (c), the synthesis of compound 5 Process 1

A/,A/-Dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide 5. A mixture of carboxylic acid 4 (2.30 g, 10 mmol) and EtOAc (20 ml) was stirred at ambient temperature and carbonyldiimidazole (2.43 g, 15 mmol, 1.5 equiv.) was added. The slurry was stirred at 60 °C for 30 minutes with some evolution of gas. To the EtOAc suspension was added dimethylamine solution (2M in THF, 10 ml, 20 mmol, 2.0 equiv.) over 5 minutes. The resulting mixture was further stirred at 60 °C for 1 hour. Meanwhile in a separate vessel EtOH (5 ml) and EtOAc (45 ml) were mixed together. The EtOAc / THF solution was cooled to room temperature, at which point a precipitate formed. Citric acid (2.10 g, 10 mmol) followed by 2M aqueous MgS0 solution (10 ml.) were then added and the mixture was stirred for 15 minutes. The mixture was allowed to stand and the organic layer was separated. The aqueous layer was then extracted by 20 ml of the EtOAc/EtOH mixture, and then an additional 10 ml of the EtOAc/EtOH mixture. THF and EtOH were removed from the combined organic phases by distillation (keeping a constant volume by adding EtOAc) until the quantity of THF and EtOH in the mixture was < 1 % with respect to EtOAc as measured by ¹ H NMR. At this point some precipitate formed and the mixture was concentrated to ca 10 ml, then cooled to room temperature. The resulting slurry was stirred overnight, and the solids were filtered to yield the amide 5 as a solid (1 .99 g, 77%). d _H (500 MHz, CDCI ) 8.15 (1 H, s), 7.87 (1 H, d, J 6.5), 7.47-7.30 (4H, m), 6.47 (1 H, d, 6.5), 5.12 (2H, s), 3.09 (3H, s), 2.95 (3H, s); d ₀ (125 MHz, CDCI ₃ ) 170.8, 160.8, 153.4, 151.0, 136.6, 136.4, 128.1 , 127.8, 116.2, 49.4, 39.5, 35.3.

Process 2

A/,A/-Dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide 5.

A mixture of carboxylic acid 4 (2.30 g, 10 mmol) and EtOAc (20 ml) was stirred at ambient temperature and carbonyldiimidazole (2.43 g, 15 mmol, 1.5 equiv.) was added. The slurry was stirred at 60 °C for 30 minutes with some evolution of gas. To the EtOAc suspension was added THF (10 ml), dimethylamine hydrochloride (20 mmol, 2.0 equiv.) and triethylamine (20 mmol, 2.0 equiv.). The resulting mixture was further stirred at 60 °C for 1 hour. Meanwhile in a separate vessel EtOH (5 ml) and EtOAc (45 ml) were mixed together. The EtOAc / THF solution was cooled to room temperature, at which point a precipitate formed. Citric acid (4.20 g, 20 mmol) followed by 2M aqueous MgS0 ₄ solution (20 ml.) were then added and the mixture was stirred for 15 minutes. The mixture was allowed to stand and the organic layer was separated. The aqueous layer was then extracted by 20 ml of the EtOAc/EtOH mixture, and then an additional 10 ml of the EtOAc/EtOH mixture. THF and EtOH were removed from the combined organic phases in vacuo to give a solid (1 .94 g, 75%). d _H (500 MHz, CDCI ₃ ) 8.15 (1 H, s), 7.87 (1 H, d, 6.5), 7.47-7.30 (4H, m), 6.47 (1 H, d, J 6.5), 5.12 (2H, s), 3.09 (3H, s), 2.95 (3H, s); d ₀ (125 MHz, CDCI ₃ ) 170.8, 160.8, 153.4, 151.0, 136.6, 136.4, 128.1 , 127.8, 116.2, 49.4, 39.5, 35.3. Process 3

A/,A/-Dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide 5.

A mixture of carboxylic acid 4 (818.1 g) and EtOAc (7100 ml) was stirred at 15 °C and carbonyldiimidazole (867.2 g) was added. The slurry was stirred at 60 °C over 1 hour and then for an additional 3 hours at this temperature with some evolution of gas. To the EtOAc suspension was added dimethylamine solution (2M in THF, 3540 ml) over 15 minutes. The resulting mixture was further stirred at 60 °C for 19 hours. The reaction was then allowed to cool to 25 °C over 2 hours. Citric acid monohydrate (820 g) was then added to the reaction, followed by aqueous magnesium sulfate solution (2M, 3000 ml). The mixture was then stirred vigorously for 20 minutes. The phases were separated and the aqueous phase was extracted with 7000 ml of EtOAc/EtOH mixture (90% EtOAc / 10% EtOH by volume), and then an additional 3500 ml of the same mixture. The combined organic phases were filtered, and the solvent was reduced in vacuo to 3500 ml. EtOAc (3500 ml) was added to the flask and again the solvent was reduced in vacuo to a volume of 3500 ml. Additional EtOAc (3500 ml) was added to the flask and again the solvent was reduced in vacuo to a volume of 3500 ml. The resulting slurry was stirred at 20 °C for 1 hour and then filtered. The solid filter cake was washed with EtOAc (1660 ml and 820 ml) and then the solid was dried on the filter in an atmosphere of nitrogen gas for 17 hours, to give amide 5 as a solid (669.6 g).

Example 4a: Large scale synthesis of compound 5

Step a A reaction vessel was charged with 4-hydroxypyrimidine 1 (0.45wt, 1.08eq) and DMSO (13.3 vol., 14.6wt) and the temperature was adjusted to between 15 ^e C and 25 ^e C. The total volume of the reaction mixture was 13.8 vol. In the process described in step (a), Vol. refers to the volume relative to the mass of Methyl 4-(bromomethyl)benzoate 2).

Solid Sodium hydroxide (0.19wt, 1.0eq) was added to the reaction vessel and the reaction mixture was kept at a temperature between 15 ^e C and 25 ^e C. The total volume of the reaction mixture was 14.0 vol. The reaction mixture was stirred for at least 30 minutes while maintaining a temperature between 15 ^e C and 25 ^e C.

Methyl 4-(bromomethyl)benzoate 2 (1.00 wt, 1 .0 eq) was added to the reaction vessel in four portions, each portion containing 0.25wt (0.2eq). The contents of the vessel was stirred for 15 minutes between the addition of each of the four portions, and the contents of the vessel was maintained at a temperature between 15 ^e C and 30°C. The contents of the vessel was adjusted to a temperature between 15 ^e C and 25 ^e C and stirred until conversion of greater than 99% of the reactants was achieved as measured by ¹ H NMR. Typically the reaction time was between 30 minutes and 2 hours. The total volume in the flask following the four additions was 15.0 vol. Purified water (USP grade) (4.4vol, 4.4wt) was added to the reaction vessel and the reaction mixture was maintained at a temperature from 15 ^e C to 30 ^e C for at least 30 minutes. The total volume in the flask following addition of the purified water was 19.5 vol. The contents of the vessel was adjusted to a temperature between 15 ^e C and 25 ^e C and stirred for at least 2 hours, and ideally between 2 and 3 hours.

The reaction mixture was then filtered over 20pm cloth and the resulting filter cake washed with purified water (USP grade) (3 x 1.Ovol, 3 x 1.Owt) at 15 ^e C to 25 ^e C. The resulting washed filter cake was dried at 25 ^e C until it could be removed from the filter and isolated as Methyl 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzoate 3. The resulting compound was analysed by ¹ H NMR to determine yield and residual DMSO content.

As shown in Table 1 A, the process outlined above led to a large scale output (223.5g) having a high yield and purity. Step B

Purified water (USP grade) (3.4wt, 3.4vol) was added to a reaction vessel and the contents adjusted to a temperature from 15 ^e C to 25 ^e C. Concentrated sulphuric acid (1.3wt, 0.7vol) was added to the reaction vessel and the contents maintained at a temperature between 15 ^e C and 25 ^e C. The total volume of the contents within the reaction vessel was 4.0 vol. In the process described in step (b), Vol. refers to the volume relative to the mass of Methyl 4- ((6-oxopyrimidin-1 (6H)-yl)methyl)benzoate 3.

Methyl 4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzoate 3 (1.0wt) was added to the reaction vessel and the reaction mixture was maintained at a temperature between 15 ^e C and 25 ^e C, targeting 15 ^e C. The resulting reaction mixture had a volume of 5.0 vol. The resulting reaction mixture was in the form of a slurry. The applicant has found that reversing the addition steps such that a dilute sulphuric acid is added to compound 3 led to a very thick slurry that would be difficult to process.

The contents of the vessel was heated to a temperature between 70 ^e C and 85 ^e C, targeting 75 ^e C, for around 1 hour.

The vessel was placed under vacuum (ca 300 to 400mBar) until gentle reflux was observed, and the reaction mixture was maintained at a temperature of from 70 ^e C to 85 ^e C. The distillation rate was circa 0.1 to 0.5 vol./hour. If necessary, purified water (USP grade) was added to the reaction vessel to maintain the volume of the reaction mixture at 5 vol. The distillation was continued for between 12 to 18 hours until the amount of compound 3 remaining reached 0.5% or less. The contents of the reaction vessel were subsequently cooled to between 15 ^e C and 25 ^e C.

A 17.5% w/w sodium hydroxide solution (4.24 wt.) was added to the reaction vessel and the contents maintained at a temperature between 15 ^e C and 25 ^e C, leading to a total volume of 9.0 vol. The reaction mixture was aged for at least one hour, for example 1.5 hours, at a temperature from 15 ^e C to 25 ^e C, and the reaction mixture was subsequently filtered. The resulting filter cake was washed three times with purified water (USP grade) (3 vol.), and 4- ((6-Oxopyrimidin-1(6H)-yl)methyl)benzoic acid 4 was isolated.

As demonstrated in Table 1 B below, sulphuric acid conditions together with slow vacuum distillation throughout led to high yield and purity.

Step C

Compound 4 (1 .00 wt) was added to a reaction vessel together with ethyl acetate (8.7 vol.) and the mixture stirred at a temperature between 15°C and 25°C. In the process described in step (c), Vol. refers to the volume relative to the mass of compound 4.

1 ,1 ’-Carbonyldiimidazole (CDI) (1.06wt, 1.5 equiv. corrected for imidazole content) was added to the reaction mixture and the temperature maintained at 15°C to 25°C.

The reaction mixture was heated to a temperature between 55°C and 60°C and the reaction mixture stirred for at least 30 minutes. The reaction was monitored by taking 1 ml. samples of the reaction mixture, quenching the sample with 2M dimethylamine (3 ml.) in THF solution and analysing by high-performance liquid chromatography (HPLC).

Once the amount of compound 4 reached 1.1%area or lower as measured by HPLC, 2M dimethylamine solution in THF (4.3vol, 2 equiv.) was added to the reaction mixture over at least 15 minutes and the temperature of the reaction mixture was maintained at 55°C to 60°C. The reaction mixture was stirred at this temperature for at least 12 hours. The reaction mixture was then sampled and analysed by HPLC to check that 1 .0% or less of compound 4 remained.

The reaction mixture was then cooled to a temperature between 15°C and 25°C, and citric acid monohydrate (1 .00 wt) was added to the reaction vessel.

A 2M magnesium sulphate solution (3.7 vol.) was prepared and added to the reaction mixture over a period of at least 5 minutes at a temperature between 15°C and 25°C. The reaction mixture was stirred vigorously for at least 15 minutes and then the aqueous and organic phases were separated using a separating funnel. The organic phase was collected.

A 9:1 mixture of ethyl acetate and absolute ethanol was prepared. The aqueous phase was extracted by addition of the ethyl acetate/ethanol mixture (8.7 Vol.) to the aqueous phase collected by the previous separation step, and the resulting mixture was vigorously mixed for 15 minutes. The phases were then separated and the organic phase collected. The resulting aqueous phase was mixed with the 9:1 ethyl acetate/ ethanol solution (4.3 Vol.) for at least 15 minutes and the phases were separated.

The collected organic phases were filtered through two pieces of glass microfiber paper (grade GF/F ). The clarified organic phases were combined and concentrated to around 4.3 Vol by vacuum distillation using a rotary evaporator (water bath temperature 40°C). Ethyl acetate (2x 4.3 vol.) was added to the concentrated organic phases and the mixture concentrated by vacuum distillation using a rotary evaporator (bath temperature 40°C) to a volume of around 4.3 vol to thereby form a slurry.

The supernatant layer from the concentrated mixture was sampled and analysed by ¹ H NMR to determine residual ethanol and THF content.

The slurry was transferred and aged for 1 to 2 hours at a temperature of 15°C to 25°C and filtered over two pieces of filter paper. The filter cake was washed twice with ethyl acetate (2 vol. followed by 1 vol.). The filter cake was dried under a nitrogen atmosphere for at least 12 hours until the amount of ethyl acetate was 2% w/w or lower as determined by ¹ H NMR analysis, to yield A/,A/-Dimethyl-4-((6-oxopyrimidin-1 (6H)-yl)methyl)benzamide 5. The resulting solid was analysed by ¹ H NMR to determine %w/w, which was used to determine the corrected output weight and yield.

Example 5: Process for the preparation of crystalline form 1 of compound 5

Amide 5 (675 g) was added to ethanol (10500 ml) and the mixture was heated to 70 °C over 1 hour, and then for an additional 15 minutes at this temperature. The mixture was then cooled to 50 °C over 1 hour and then filtered at this temperature. The solvent was reduced in vacuo to a volume of 2000 ml. This mixture was then heated to 70 °C over 15 minutes to achieve dissolution. The mixture was cooled to 60 °C over 30 minutes and then seed crystals obtained from a previous reaction (3.4 g) were added. The mixture was stirred at 60 °C for 30 minutes to initiate crystallization, and then the mixture was cooled to 5 °C over 2 hours. The slurry was then filtered at that temperature and the filter cake was washed with ethanol (5 °C, 700 ml and 350 ml). The solid was dried on the filter in an atmosphere of nitrogen gas for 19 hours, to give amide 5 as a solid (585 g) as crystalline form 1 .

Example 6: Analysis of crystalline form 1 of compound 5 by X-ray powder diffraction

A sample of crystalline form 1 of compound 5 was collected and an X-ray powder diffractogram was collected using a Bruker D8 diffractometer using Cu Ka radiation (40 kV, 40 mA) and a Q-2Q goniometer fitted with a Ge monochromator. The incident beam passed through a 2.0 mm divergence slit followed by a 0.2 mm anti-scatter slit and knife edge. The diffracted beam passed through an 8.0 mm receiving slit with 2.5° Soller slits followed by the Lynxeye Detector. The software used for data collection and analysis was Diffrac Plus XRD Commander and Diffrac Plus EVA respectively.

Samples were analysed under ambient conditions as flat plate specimens.

The Pharmorphix data collection method used the following parameters: Angular range: 2 to 42° 2Q

Step size: 0.05° 2Q

Collection time: 0.5 s/step (total collection time: 6.40 min)

The XRPD diffractogram is shown below in Figure 1 , and a table of peak values and intensities is set out below as Table 2. Example 7: Analysis of crystalline form 1 of compound 5 by single crystal x-ray diffraction Single crystals of crystalline form 2 of compound 5 were grown from water.

A suitable crystal was selected and mounted on a glass fibre with Fomblin oil and placed on an Xcalibur Gemini diffractometer with a Ruby CCD area detector. The radiation source was Cu Ka. The crystal was kept at 160(2) K during data collection. Using Olex2 [1 ], the structure was solved with the SheIXT [2] structure solution program using Intrinsic Phasing and refined with the SheIXL [3] refinement package using Least Squares minimisation.

Crystal Data for Form 1 of compound 5:

C ₁₄ H ₁₅ N ₃ O ₂ (M =257.29 g/mol): monoclinic, space group P2i/n (no. 14), A,a = 6.06802(8) A, b= 31 .6418(3) A, c= 7.09782(11 ) A, b = 113.6214(16)°, \/ =

1248.62(3) A ³ , Z= 4, T= 160(2) K, p(CuKa) = 0.767 mm Dcalc= 1.369 g/cm ³ , 21486 reflections measured (5.586° < 2Q < 156.138°), 2652 unique (flin _t = 0.0327, R _Sigma = 0.0155) which were used in all calculations. The final fli was 0.0373 (I > 2s(I)) and wfl ₂ was 0.1027 (all data).

The numbering of atoms shown in Table 4 is illustrated in Figure 3.

Example 8: Process for the preparation of crystalline form 2 of compound 5 Amide 5 was recrystallizes from hot ethyl acetate to produce a solid as crystalline form 2.

Example 9: Analysis of crystalline form 2 of compound 5 by X-ray powder diffraction

A sample of crystalline form 2 of compound 5 was collected and an X-ray powder diffractogram was collected using a Bruker D8 diffractometer using Cu Ka radiation (40 kV, 40 mA) and a Q-2Q goniometer fitted with a Ge monochromator. The incident beam passed through a 2.0 mm divergence slit followed by a 0.2 mm anti-scatter slit and knife edge. The diffracted beam passed through an 8.0 mm receiving slit with 2.5° Soller slits followed by the Lynxeye Detector. The software used for data collection and analysis was Diffrac Plus XRD Commander and Diffrac Plus EVA respectively.

Samples were analysed under ambient conditions as flat plate specimens. The Pharmorphix data collection method used the following parameters:

Angular range: 2 to 42° 2Q

Step size: 0.05° 2Q

Collection time: 0.5 s/step (total collection time: 6.40 min) The XRPD diffractogram is shown below in Figure 2, and a table of peak values and intensities is set out below as Table 5.

Example 10: Analysis of crystalline form 2 of compound 5 by single crystal x-ray diffraction

Single crystals of crystalline form 2 of compound 5 were grown from ethyl acetate. A suitable crystal was selected and mounted on a glass fibre with Fomblin oil and placed on an Xcalibur Gemini diffractometer with a Ruby CCD area detector. The crystal was kept at 150(2) K during data collection. Using Olex2 [1 ], the structure was solved with the SheIXT [2] structure solution program using Intrinsic Phasing and refined with the SheIXL [3] refinement package using Least Squares minimisation.

Crystal data for crystalline form 2 of compound 5

Crystal Data for C ₁₄ H ₁₅ N ₃ O ₂ (M = 257.29 g/mol): triclinic, space group P-1

(no. 2), a = 6.10847(17) A, b= 9.3268(2) A, c= 11.4631(3) A, a = 88.5232(19)°, b = 81.396(2)°, y= 81.211 (2)°, V= 638.15(3) A ³ , Z= 2, T= 150(2) K, p(CuKa) = 0.751 mnr

¹ , Dcalc = 1.339 g/cm ³ , 22962 reflections measured (7.8° < 2Q < 155.876°), 2696 unique (flint = 0.0787, Rsigma = 0.0334) which were used in all calculations. The final fli was 0.0502 (I > 2o(l)) and wfl ₂ was 0.1469 (all data).

The numbering of atoms shown in Table 7 is illustrated in Figure 4.

References [1] Dolomanov, O.V., Bourhis, L.J., Gildea, R.J, Howard, J.A.K. & Puschmann, H.

(2009), J. Appl. Cryst. 42, 339-341.

[2] Sheldrick, G.M. (2015). Acta Cryst. A71 , 3-8.

[3] Sheldrick, G.M. (2015). Acta Cryst. C71 , 3-8.