Particularly these compounds are more specific for said CB2 receptor class than many other compounds active on cannabinoid receptors CB1 and CB2.

At least five different classes of cannabinoids have been identified; traditional tricyclic tetrahydrocannabinoids, such as A9-tetrahydrocannabinoid (A9- THC), synthetic bicyclic cannabinoids such as CP55,940 (see Little et al (1988) ), aminoalkylindole such as WIN55, 212 (see D'Ambra et al (1992) ), endocannabinoid such as anandamide (see Devane et al (1992) ), and pyrazol antagonists such as SR141716A (see Rinaldi-Carmona (1994) ). Although the chemical structure of these cannabinoids differ markedly, all of them contain at least one oxygen that is hypothesized to be involved in binding of these drugs to brain cannabinoid (CB1) receptors.

A9-THC, the primary psychoactive constituent of the marijuana plant, and other tetrahydrocannabinols contain two oxygens; a phenolic hydroxyl at position 1 and an oxygen pyran ring on the opposite side of the molecule. The hydroxyl oxygen interacts with the CB1 receptor through hydrogen bonding with a lysine residue (Lys 192) (see Song and Bonner (1996) ). The role of the oxygen of the benzopyran substituent of A9-THC is less clear ; however it is known that opening of the pyran ring as in CP55,940 does not eliminate binding or in vivo activity (See Little et al (1988) ). In the absence of a phenolic hydroxyl, as in 1-deoxyanalogs of A8-THC, orientation of the cannabinoid molecule with respect to the CB1 receptor may be inverted and the pyran oxygen may substitute as a substrate for hydrogen bonding with Lys 192 (see Huffman et al (1996), (1999)).

In contrast to the high binding affinity of CP55, 940 and other similar pyran- ring open analogs the natural product cannabidiol is also a pyran-ring open compound yet does not bind to CB1 or CB2 receptors nor does it have a cannabinoid profile of effects in vivo. Even the 1', 1'-dimethylheptyl analog of cannabidiol binds very poorly to the CB1 receptor. With this in mind the present

inventors have studied the structural activity relationship of resorcinol derivatives which could be considered as cannabidiol analogs.

During this study, Hanu et al (1999) published synthesis and activity of HU- 3-8, a dimethoxyresorcinol derivative that is a CB2 selective agonist. The transmembrane regions of CB2 receptors, which are involved in ligand recognition, exhibit 68% homology with those of CB1 receptors (see Munro et al (1993) ).

Showalter et al (1996) reported a high positive correlation (r=0.82) between binding affinities at these two cannabinoid receptors for cannabinoids in various classes; thus some of the structural features that enhance affinity for CB1 also enhance affinity for CB2.

Addition of a 1', 1'-dimethyl group to the lipophilic C3 side chain of A8-THC results in higher affinity for both receptors as compared to a nonbranched chain of identical length. Synthesis of a series of A8-THC analogs in which the phenolic hydroxyl at position 1 was removed (deoxy-A8-THC analogs) or was replaced with a methoxy ! resulted in analogs with selectivity for CB2 receptors (see Gareau et al (1996); Huffman et al (1996) (1999)). Incorporation of an oxygen into a fourth ring attached at C1 also increased CB2 selectivity, suggesting differences in the interaction of oxygen in the binding pockets of CB1 and CB2 (see Reggio et al (1997)).

The present inventors have now provided bicyclic resorcinols in which the core chemical structure contains two hydroxyl substituents positioned with a single intervening carbon in a benzene ring with a second cyclic substituent attached at the intermediate carbon.

In a first aspect of the present invention are provided novel compounds of general formula I

wherein: R is selected from the group consisting of optionally substituted carbocyclic and heterocyclic rings; R1 is independently selected at each occurrence from the group consisting of hydrogen and C16 alkyl ; R4 is selected from the group consisting of C110 alkyl or alkenyl ; and pharmaceutical acceptable salts, esters and tautomers thereof.

Preferred compounds of the invention have R as optionally substituted aryl, e. g. phenyl, cyclohexyl, cycloheptyl, cyclohexenyl, cyclopentyl, tetrahydrothiopyranyl, methandienyl, cycloheptyl, adamantanyl, tetrahydrothiophen-3-yl, 1-alkyl-piperidinyl, 4-aryl-cyclohexyl, 3, 3-dialkylcyclohexyl, tetrahydropyranyl, 1-cyclohexanolyl, 1-4-dioxospirocycloalkyl, and cyclohex-3- enonyl.

Preferred compounds of the invention have R1 as hydrogen or methyl.

Preferred compounds of the invention have R4 as linear C 5 7 alkyl, e. g., hexyl.

A preferred group of novel compounds of the first aspect of the invention are of general formula 11

wherein R1 and R4 are as described for formula I and R5 is C16 alkyl, more preferably methyl or ethyl. More preferably R1 is hydrogen or methyl, more preferably hydrogen. All isomers of compounds of formula 11 are of interest, but particularly preferred are isomer A and isomer B and the 3R-alkylcyclohexyl compounds, particularly compounds of formula 2-(3-methylcyclohexyl)-5-(1, 1'-dimethylheptyl)-resorcinol isomer A (0-1797) 2- (3-methylcyclohexyl)-5- (1, 1'-dimethylheptyl)-resorcinol isomer B (0-1798) 2- (3R-methylcyclohexyl)-5- (1, 1'-dimethylheptyl)-resorcinol (0-1826).

A second aspect of the present invention provides a method of treating a patient in need of therapy for pain, particularly peripheral pain and/or inflammation or autoimmune disease comprising administering to that patient a therapeutical effective amount of a compound of formula 1, more preferably of formula 11. Such amount will typically be administered in a pharmaceutically acceptable carrier, such as is well known in the art.

A third aspect of the present invention provides a composition comprising a compound of formula I or 11 together with a pharmaceutical acceptable carrier and/or excipient. The composition should be sterile and, if intended for injection, non-pyrogenic.

Administration of the aforementioned compounds of the invention or a formulation thereof need not be restricted by route. Options include enteral (for example oral and rectal) or parenteral (for example delivery into the nose or lung or injection into the veins, arteries, brain, spine, bladder, peritoneum, muscles or subcutaneous region). The treatment may consist of a single dose or a plurality of doses over a period of time. The dosage will preferably be determined by the physician but may be between 0.01 mg and 1.0 g/kg/day, for example between 0.1 and 500 mg/kg/day. In terms of dose per square meter of body surface, the compound can be administered at 1.0 mg to 1.5 g per m2 per day, for example 3.0- 200.0 mg/m2/day.

Whilst it is possible for a compound of the invention to be administered alone, it is preferable to present it as a pharmaceutical formulation, together with one or more acceptable carriers and/or excipients. The carrier (s) and/or excipients must be"acceptable"in the sense of being compatible with the compound of the invention and not deleterious to the recipients thereof.

The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. A unit dosage form may comprise 2.0 mg to 2.0 g, for example 5.0 mg to 300.0 mg of active ingredient. Such methods include the step of bringing into association the active ingredient, i. e. , the compound of the invention, with the carrier and/or excipients which constitute one or more accessory ingredients. In general the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers and/or excipients and/or two or all of these, and then, if necessary, shaping the product.

Formulations in accordance with the present invention suitable for oral administration may be presented as discrete units such as capsules, cachets or tablets, each containing a predetermined amount of the active ingredient; as a powder or granules ; as a solution or a suspension in an aqueous liquid or a non- aqueous liquid ; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient may also be presented as a bolus, electuary or paste.

A tablet may be made by compression or molding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by

compressing in a suitable machine the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder (e. g. povidone, gelatin, hydroxypropyl-methyl cellulose), lubricant, inert diluent, preservative, disintegrant (e. g. sodium starch glycollate, PVP, cross-linked povidone, cross-linked sodium carboxymethyl cellulose), surface-active or dispersing agent. Molded tablets may be made by molding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may optionally be coated or scored and may be formulated so as to provide slow or controlled release of the active ingredient therein using, for example, hydroxypropylmethylcellulose in varying proportions to provide desired release profile.

Formulations suitable for topical administration in the mouth include lozenges comprising the active ingredient in a flavored basis, usually sucrose and acacia or tragacanth; pastilles comprising the active ingredient in an inert basis such as gelatin and glycerin, or sucrose and acacia; and mouth-washes comprising the active ingredient in a suitable liquid carrier.

Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which may render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described.

Preferred unit dosage formulations are those containing a daily dose or unit, daily sub-dose or an appropriate fraction thereof, of an active ingredient.

It should be understood that in addition to the ingredients particularly mentioned above the formulations of this invention may include other agents conventional in the art having regard to the type of formulation in question, for example those suitable for oral administration may include flavoring agents.

In a fourth aspect of the present invention there is provide a compound of the first aspect of the invention for use in therapy.

In a fifth aspect of the present invention there is provided the use of a compound of the first aspect of the invention for the manufacture of a medicament for the treatment of a pain, inflammation and autoimmune disease.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be described further by reference to the following non-limiting examples and Figures. These are provided for the purpose of illustration only and other examples falling within the scope of the claims will occur to those skilled in the art in the light of these. All literature references cited herein are incorporated by reference.

Figure 1 shows Chemical structures of A9-THC, CP 55,940, and cannabidiol ; Figure 2 shows a scheme for synthesis of resorcinol analogs; Figure 3 shows scatterplots and regression lines of log CB1 Kj plotted against log CB2 Ki (top left panel) and log EDgo for each of the three in vivo tests (SA = spontaneous activity, top right panel ; MPE = % maximum possible antinociceptive effect, bottom left panel ; RT = change in rectal temperature, bottom right panel) ; and Figure 4 shows a cannabinoid receptor (CB2) selective resorcinol derivative.

DETAILED DESCRIPTION OF THE INVENTION Subjects Male ICR mice (25-32g), obtained from Harlan (Dublin, VA), were housed in groups of five. All animals were kept in a temperature-controlled (20-22°C) environment with a 12-hour light-dark cycle (lights on at 7 a. m. ). Separate mice were used for testing each drug dose in the in vivo behavioral procedures. Brain tissue for binding studies was obtained from male Sprague-Dawley rats (150-200 g) purchased from Harlan Laboratories (Dublin, VA).

Apparatus Measurement of spontaneous activity in mice occurred in standard activity chambers interfaced with a Digiscan Animal Activity Monitor (Omnitech Electronics, Inc., Columbus, OH). A standard tail-flick apparatus and a digital

thermometer (Fisher Scientific, Pittsburgh, PA) were used to measure antinociception and rectal temperature, respectively.

Compounds Resorcinols were synthesized in our labs (Organix, Inc., Woburn, MA) according to the procedure specified below and were suspended in a vehicle of absolute ethanol, Emulphor-620 (Rhone-Poulenc, Inc., Princeton, NJ), and saline in a ratio of 1: 1: 18. Drugs were administered to the mice intravenously (i. v. ) in the tail vein at a volume of 0.1 ml/10g.

Analogs 0-1376 and 0-1532 listed in Table 1 were synthesized as previously described (Mahadevan et al., 2000). Analog 0-1601 was synthesized from 1-deoxy-9-carbomethoxy cannabinol DMH analog (Mahadevan et al., 2000) by lithium/liquid ammonia reduction as described'for the preparation of 0-1376.

The compounds listed in Tables 2 and 3 were prepared using a three step sequence (Figure 1). The 2-litho derivative of 1, 3-dimethoxy-5- (1', 1'- dimethylheptyl) resorcinol (1) was prepared using n-BuLi/hexane in THF. It was condensed with the appropriate ketone to give the tertiary alcohol 2, which on treatment with trifluoroacetic acid/Et3SiH gave the dimethoxy precursors 3.

Demethylation2 with BBr3/CH2CI2 gave the target compounds (Crocker et al., 1999). The general procedure is illustrated in Figure 2 and described below.

To a solution of the resorcinol 1, (5 mmol) in 25 mi of dry THF was added a 2.5 M solution of n-BuLi in hexane (5. 5mmol) at 0 °C with stirring/N2. After additional stirring for 1 h at 0 °C, added a solution of the ketone (7.5 mmol) in 3 ml of dry THF all at once. The solution was stirred for 0.5 h at 0 °C and then at 23 °C for 18 h. The reaction was worked up by the addition of sat NH4CI solution and extracted with ether. After washing (H20) and drying (Na2SO4) the solvent was evaporated to give the crude tertiary alcohol 2, which was used as such in the subsequent reaction. A solution of the tertiary alcohol 2 (5 mmol) in 10 ml of dry CH2CI2 was treated with CF3COOH (27.5 mmol) followed by Et3SiH (12.5 mmol).

The solution was stirred/N2 for 1 h or more (followed by TLC) and then quenched by the addition of sat NaHCO3 solution. The organic layer was separated and after washing (H20) and drying gave the crude dimethoxy precursor 3 of the target compound. This material was used as such for the demethylation step. Treatment of 3, as a solution in dry CH2CI2 at 0 °C, with 3 equivalents of 1 N BBr3 solution in

CH2CI2, using the standard procedure and work up2, gave the crude target compound, which was purified by chromatography, generally using hexane/ethyl acetate mixtures. In the case of 0-1662 (Table 2), the corresponding tertiary alcohol 2 on treatment with CF3COOH/Et3SiH gave the unsaturated compound (dehydrated but not reduced) which on catalytic reduction (PtO2/C/H2) in acetic acid gave the desired dimethoxy precursor 3. The final compound was purified by chromatography using 5% Et3NH2/EtOAc mixture. The unsaturated analog 0- 1423 (Table 2) was prepared by treatment of the corresponding tertiary alcohol 2 with CF3COOH alone in CH2CI2 followed by demethylation. In Table 3, compounds 0-1797-A and 0-1798-B were diastereomeric mixtures and showed as two distinct spots in TLC which were separated by column chromatography, whereas 0-1657 was a sample of the mixture of diastereomers 0-1797-A and 0-1798-B. The dimethoxy compounds listed in Tables 4 and 5 were prepared (Figure 2) from 1 and the appropriate ketones using BuLi, as in the preparation of 2, and isolating and purifying the compounds by chromatography (ethyl acetate/hexane mixtures).

Deprotection of 0-2092 was carried out by treatment with 10% HCI in a ether/THF (5: 4) mixture for 0.5 h at 23 °C to give a mixture of 0-2115 (major) and the dehydrated compound 0-2114 (minor). Sodium borohydride reduction of 0-2115 furnished a mixture of diastereomeric compounds which were separated by chromatography to give the target compounds 0-2116-A and 0-2117-B. Similarly 0-1966-A and 0-1967-B were separated from a diastereomeric mixture by chromatography. Epoxidation of 0-2114 followed by NaBH4 reduction gave the target compound 0-2122. In the preparation of 0-2090 the corresponding diethoxy resorcinol derivative of 1 was used in place of 1. All compounds showed appropriate'HNMRs (Jeol Eclipse 300 MHz) and were characterized on the basis of their 1HNMRs, TLC, and elemental analyses.

Mouse Behavioral Procedures Prior to testing in the behavioral procedures, mice were acclimated to the experimental setting (ambient temperature 22-24°C) overnight. Pre-injection control values were determined for rectal temperature and tail-flick latency (in sec).

Five min after i. v. injection with drug or vehicle, mice were placed in individual activity chambers and spontaneous activity was measured for 10 min. Activity was

measured as total number of interruptions of 16 photocell beams per chamber during the 10-min test and expressed as % inhibition of activity of the vehicle group. Tail-flick latency was measured at 20 min post-injection. Maximum latency of 10 sec was used. Antinociception was calculated as percent of maximum possible effect {% MPE = [(test-control latency)/ (10-control)] X 100}. Control latences typically ranged from 1.5 to 4.0 sec. At 30 min post-injection, rectal temperature was measured. This value was expressed as the difference between control temperature (before injection) and temperatures following drug administration (°C). Different mice (n=5-6 per dose) were tested for each dose of each compound. Each mouse was tested in each of the 3 procedures.

CB1 Binding Procedure The methods used for tissue preparation and binding have been described previously (Compton et al., 1993) and are similar to those described by Devane et al. (1988). All assays, as described briefly below, were performed in triplicate, and the results represent the combined data from three to six individual experiments.

Following decapitation and rapid removal of the brain, whole brain was homogenized and centrifuged. The resulting pellet was termed P1. The supernatant was saved and combined with the two subsequent supernatants obtained from washing of the P1 pellet. The combined supernatant fractions were centrifuged, resulting in the P2 pellet. After further incubation and centrifuging, this pellet was resuspended in assay buffer to a protein concentration of approximately 2 mg/ml. The membrane preparation was quickly frozen in a bath solution of dry ice and 2-methylbutane (Sigma Chemical Co. , St. Louis, MO), then stored at-80 °C for no more than 2 weeks. Prior to performing a binding assay an aliquot of frozen membrane was rapidly thawed and protein values determined by the method of Bradford (1976).

Binding was initiated by the addition of 150 g of P2 membrane to test tubes containing 1 nM of [3H] CP 55,940 (79 Ci/mmol) and a sufficient quantity of buffer to bring the total incubation volume to 1 ml. Nonspecific binding was determined by the addition of 1 M unlabeled CP 55,940. Following incubation at 30°C for 1 hr, binding was terminated by addition of ice cold buffer and vacuum filtration through pretreated filters in a 12-well sampling manifold (Millipore, Bedford, MA). After washing, filters were placed into plastic scintillation vials

(Packard, Downer Grove, IL) and shaken. The quantity of radioactivity present was determined by liquid scintillation spectrometry.

CB Binding Procedure Membranes for CB2 binding were obtained from CHO cells. The transfected cell line was maintained in Dublecco's Modified Eagle Medium (Gibco BRL, Grand Island, NY) with 10% fetal clone II (HyClone Laboratories, Inc., Logan, UT) plus 0.3 to 0.5 mg/ml G418 (to maintain selective pressure) under 5% C02 at 37% C.

Cells were harvested with 1 mM EDTA in phosphate-buffered saline and were centrifuged at 1000 X g for 5 min at 4% C. The supernatant was saved and the P1 pellet was resuspended in centrifugation buffer. Homogenization and centrifugation were repeated twice and the combined supernatant fractions were centrifuged at 40,000 X g for 30 min at 4% C. The P2 pellet was resuspended in centrifugation buffer 2 (Tris HCI, 50 mM; EDTA, 1 mM; and MgCtz, 3 mM, pH 7.4) to a protein concentration of approximately 2 mg/ml. Protein concentrations were determined by the method of Bradford (1976) using Bio-Rad Protein Assay (Bio- Rad, Richmond, CA) and BSA standards (fatty acid free, Sigma Chemical Co. , St.

Louis, MO). The membrane preparation was divided into amounts convenient for binding assays and frozen rapidly in dry ice and stored at-80% C.

Binding was initiated by the addition of 50 g of quickly thawed P2 membranes to test tubes containing [3H] CP-55,940 (final reaction concentration 0.5 nM), an appropriate concentration of unlabeled CP-55,940 or test drug, and sufficient quantity of assay buffer (50 mM Tris-HCI, 1 mM EDTA, 3 mM MgCl2, 5 mg/ml bovine serum albumin, pH 7.4) to bring the total incubation volume to 0.5 ml. Concentration of [3H] CP-55,940 in saturation studies ranged from 50 to 10,000 pM. Nonspecific binding was determined by the addition of 1 M unlabeled CP- 55,940. CP-55,940 and all cannabinoid analogs were prepared by suspension in assay buffer from a 1 mg/ml ethanolic stock without evaporation of the ethanol (final concentration of no more than 0.4%). In competition studies, analog concentrations ranged from 0.1 nM to 10 M. After incubation at 30% C for 1 hr, binding was terminated by the addition of 2 ml of ice-cold wash buffer (50 mM Tris- HCI and 1 mg/ml BSA) and vacuum filtration through pre-treated filters in a 12-well sampling manifold (Millipore, Bedford, MA). Reaction vessels were washed once with 2 ml of ice-cold wash buffer. Filters were placed into 7-ml plastic scintillation

vials (RPI Corp. , Mount Prospect, IL) with 4 ml of Budget-Solve (RPI Corp. ). After shaking for 30 min, the radioactivity present was determined by liquid scintillation spectrometry. Three reaction vessels were used for each drug concentration in each assay. The results represent the combined data of three independent experiments. All assays were performed in siliconized test tubes, which were prepared by air drying (12 hr) inverted borosilicate tubes after two rinses with a 0. 1 % solution of AquaSil (Pierce, Rockford, IL). The GF/C glass-fiber filters (2.4 cm, Baxter, McGaw Park, IL) were pre-treated in a 0. 1% solution of pH 7.4 polyethylenimine (Sigma Chemical Co. ) for at least 6 hr.

Data Analysis Based on data obtained from numerous previous studies with cannabinoids, maximal cannabinoid effects in each procedure were estimated as follows : 90% inhibition of spontaneous activity, 100% MPE in the tail flick procedure, and-6°C change in rectal temperature. ED50's were defined as the dose at which half maximal effect occurred. For drugs that produced one or more cannabinoid effect, ED50's were calculated separately using least-squares linear regression on the linear part of the dose-effect curve for each measure in the mouse tetrad, plotted against loglo transformation of the dose. For the purposes of potency comparison, potencies were expressed as limol/kg.

Pearson product-moment correlation coefficients (with associated significance tests) were calculated between CB1 binding affinity (expressed as log Kj) and in vivo potency for each measure (expressed as log ED5o in tmol/kg) for all active cannabinoid compounds that bound to the CB, receptor. In addition, multiple linear regression was used to calculate the overall degree of relationship between CB1 binding affinity and potency in the mouse measures for all active cannabinoids. A correlation between CB1 and CB2 binding affinities was calculated for all compounds that had measurable Ki's for CB1 and CB2 binding (Kj < 10,000 nM). Ki values for CB1 and CB2 binding were obtained from Scatchard displacement analysis as determined via EBDA program of the KELL software package (Biosoft, Milltown, NJ).

The CB1 and CB2 binding affinities for substituted biphenyl analogs are shown in Table1. These compounds contain a phenolic hydroxyl and a lipophilic

side chain in the same orientation as in cannabinol. In addition, the pyran oxygen is absent and the analogs have substituents in the phenyl ring (ring C) of cannabinol. Two of the analogs (0-1376 and 0-1601) have a dimethylheptyl side chain; each possessed good CB1 and CB2 binding affinities and in vivo activity. O- 1601, the more potent of the two active compounds, had a hydroxymethyl group in the phenyl ring. This substitution increased CB1 affinity and in vivo potencies compared to 0-1376, but did not affect affinity for CB2 receptors. A similar effect is observed in the cannabinol series where the substitution of a hydroxymethyl group for a methyl at C-9 in cannabinol increased binding affinity and potency (Mahadevan et al., 2000). Shortening the side chain of 0-1376 to dimethylbutyl (0-1532) severely decreased affinity for both receptors and resulted in loss of in vivo activity.

Table 2 presents binding and in vivo data for a series of 2-cyclic ring substituted-5-dimethylheptyl resorcinols. Manipulation of the size of the cyclic structure attached at position 2 of the resorcinol ring resulted in changes in binding affinities and potencies. Substitution of a cyclopentane ring (0-1424) resulted in moderate affinity for the CB1 receptor with excellent affinity for the CB2 receptor.

Although this compound was active in all three in vivo assays, potency was relatively poor. In addition, potencies across the measures were not equal ; i. e., potency for reducing spontaneous activity was approximately half that for producing antinociceptive and hypothermic effects. Increasing ring size to a cyclohexane (0-1422), cycloheptane (0-1656), or adamantyl (0-1660) improved affinity 5-to 14-fold for both cannabinoid receptors and greatly increased potencies in vivo. Substitution of a sulfur for a carbon in a cyclohexane ring (0-1425) decreased CBi affinity by 14-fold and CB2 affinity by 8-fold (compared to 0-1422) as well as reducing in vivo potencies. Similarly, sulfur substitution in a cyclopentane ring (0-1661) also attenuated binding to both cannabinoid receptors.

When a methylated nitrogen (0-1662) was inserted into the cyclohexane ring in

the same position as the sulfur of 0-1425, binding to CB1 receptors did not occur.

In addition, CB2 binding was drastically decreased and the compound was not fully active in vivo. In contrast, placing a double bond in the cyclohexane ring (0-1423) decreased affinities and potencies, but the compound remained active. However, moving the lipophilic side chain of 0-1422 from C-5 to C-4 and replacing the DMH with a n-hexyl chain (0-2010) produced a 865-fold decrease in CB1 affinity and a loss of activity in vivo.

Table 3 shows results of tests with cyclohexane substituted resorcinols in which the position of the substituent at the cyclohexane ring attached to the core resorcinol was varied. All compounds were diastereomeric mixtures. All of these analogs had good (Kj = 2 nM) to moderate (Kj = 144 nM) affinity for CB1 receptors and were CB2-selective (Kj range = 0. 3-13 nM). Methylation at the 2 position of the cyclohexane ring (0-1658) did not dramatically alter affinity for either cannabinoid receptor or in vivo potencies compared to the corresponding cannabinoid with a non-methylated cyclohexane (0-1422 in Table 2). Moving the methyl to position 4 of the cyclohexane ring (0-1659) decreased affinity for both cannabinoid receptors by about 5-fold and produced an even greater decrease (11-to 24-fold) in potencies in vivo. Substituting a phenyl group for the methyl at this same position (0-1663) resulted in 2-to 3-fold decreases in CB2 and CB1 affinities, respectively, and a loss of activity in vivo. In the next five analogs shown in Table 3, the methyl was attached at position 3 of the cyclohexane ring. 0-1657 exhibited CB1 and CB2 affinities that were similar to those of 0-1658 ; however, the profiles of in vivo potencies differed. Whereas the two analogs showed approximately equal potencies in suppressing spontaneous activity, 0-1658 was twice as potent in producing antinociception and three times as potent in reducing body temperature. By careful chromatography, compound 0-1657 was separated into two distinct entities which were designated 0-1797-A and 0-1798-B. These analogs were still mixtures. Affinities of 0-1797-A and 0-1798-B were 2-3 times

greater than those of 0-1657. While potencies of these isomers for suppression of locomotor activity and hypothermia were not notably different from those of 0- 1657, antinociceptive potencies were reduced by about half. The 3R isomer of this series (0-1826) showed decreased affinity for CB1 receptors compared to 0-1657 ; however, affinity for CB2 receptors was identical for both compounds. Not surprisingly, given its decreased CB1 affinity, 0-1826 was less potent than 0-1657 in vivo. Substitution of a dimethylbutyl for the DMH side chain at C5 of the resorcinol component (0-1890) decreased affinities for both cannabinoid receptors. This compound was active in vivo, although potency was notably low for all measures. In contrast, addition of a gem-dimethyl group at the 3 position of the cyclohexane ring with retention of the DMH side chain of the resorcinol component (0-1871) resulted in the best CB1 and CB2 affinities of this series. In vivo potencies, however, were lower than expected for this compound, given its higher CB1 binding affinity.

In order to develop CB2 selective ligands, we examined cyclic ring substituted dimethoxy resorcinols. The CB1 and CB2 binding affinities of these analogs are shown in Tables 4 and 5. Although most of the compounds shown in Tables 4 and 5 possessed a dimethylheptyl side chain, all had poor CB1 affinity ; hence, they were not tested in vivo. The bicyclic structure of 0-1999 (Table 4) was almost identical to that of 0-1657 (Table 3), an analog with good CB1 and CB2 affinities and potent in vivo effects. Both compounds had a dimethylheptyl side chain attached to the 5 position of a resorcinol core that was attached at position 2 to a cyclohexane ring. Each compound had a methyl group at the 3 position of the cyclohexane ring. The major structural difference between the two compounds was that 0-1999 was a dimethoxy derivative of the resorcinol 0-1657. This seemingly minor structural change from a phenol to a methoxy derivative resulted in complete loss of affinity for CB1 receptors and an almost 600-fold reduction in affinity for CB2 receptors. Similarly, the other analogs that were dimethoxy

derivatives of the corresponding resorcinols had poor affinity for CB1 receptors (Kj ranged from 1716 to > 10,000), regardless of the cyclic ring substitution at position 2. In contrast, CB2 binding affinities for some of these analogs remained high, as described in more detail below.

Table 4 presents binding data for 2-cyclic ring substituted dimethoxy- resorcinol-DMH analogs that contain at least one oxygen inserted into or attached to the non-resorcinol cyclohexane ring. Compared to 0-1999 which did not contain an oxygen in the cyclohexane ring, conversion of the cyclohexane ring to a pyran ring (0-1964) decreased CB2 affinity almost 2-fold without effect on CB1 binding. Further addition of a double bond at position 3 of the pyran ring resulted in 0-1965 which did not bind to either cannabinoid receptor. In contrast, the introduction of a tertiary hydroxyl group at C-4 of the pyran ring (0-1962) increased CB2 affinity by 3-fold. Adding additional oxygens such as a ketol group attached at C-4 to the point of attachment of the dimethoxy resorcinol substituent (0-2092) also increased CB2 affinity whereas adding an oxygen as an epoxide (0-2122) decreased it. The presence of a ketone group at C-4 of the cyclohexane ring and having unsaturation in the ring (0-2114) resulted in a compound with poor affinity for either cannabinoid receptor; however, if a tertiary hydroxyl group was added at the site of dimethoxy resorcinol attachment (0-2115), CB2 affinity improved.

Retention of the tertiary hydroxyl, methylation at position 5 and the presence of a ketone at position 3 of the cyclohexane ring increased affinity for both receptors and resulted in a compound (0-2123) with the best affinity (Kì = 125 nM) in this series.

Table 5 shows CB1 and CB2 affinities for 2-cyclic ring substituted dimethoxy- resorcinol-DMH analogs in which the ring size and the position of the methyl or hydroxyl substituent on the cyclohexane ring are varied. The first analog (0-2072) contains one hydroxyl attached to the cyclohexane at the same position at which the resorcinol core is attached. This compound is CB2-selective. While it had poor

affinity for CB1 receptors, it bound with moderate affinity to CB2 receptors.

Introduction of a methyl substituent in the 3 position of the cyclohexane ring gave a diastereomeric mixture from which two distinct entities were separated by careful chromotography. These analogs (0-1966-A and 0-1967-B) were still mixtures.

This substitution resulted in a 5-fold increase in affinity for CB2 receptors with continued poor affinity for CB1 receptors. However, one of these isomers (0-1966- A) showed the best CB2 selectivity (225-fold) in the series and had high binding affinity for the CB2 receptor (K ; = 22.5 nM). Addition of an extra hydroxyl group to the cyclohexane ring (0-2121) reduced both selectivity and binding affinity for the CB2 receptor comparable to those obtained with 0-1967-B. Removal of the methyl at position 3 and addition of an hydroxyl at position 4 resulted in two diastereomeric mixtures which could be separated that were designated as 0- 2116-A and 0-2117-B. Both of these isomers had poor affinity for CB1 receptors, but while the B isomer also had poor affinity for CB2 receptors, the A isomer bound to CB2 receptors with moderate affinity. Attachment of a gem-dimethyl group to position 3 of 0-2072 (i. e., 0-2068) did not significantly alter affinities for CB, or CB2 receptors; however, replacement of the DMH group of 0-2068 with a methyl group (0-2139) produced loss of affinity at both receptors. Changing the dimethyoxy groups of the resorcin by adding diethoxy groups (0-2090) drastically decreased affinities for CB1 and CB2 receptors (compare 0-2090 to 0- 1966-A or 0-1967-B). Enlarging the cyclohexane ring in 0-2072 to a cycloheptane ring (O-2091) resulted in little change in affinity for CB1 receptors and an almost 2- fold increase in CB2 affinity.

As stated in the introduction, the lack of CB1 binding affinity of cannabidiol compared to other pyran-ring open analogs such as CP 55,940 prompted us to examine the structure-activity relationships of resorcinol derivatives for in vitro and in vivo cannabinoid activity. Our results show that many of the structural changes that affect CB1 receptor recognition and activation in traditional bicyclic and tricyclic

cannabinoids similarly alter binding and activity in this resorcinol series. Previous research has shown that the length and branching of a lipophilic substituent is important for CB1 receptor recognition in all of the major cannabinoid agonist classes, including tetrahydrocannabinols (Compton et al., 1993), bicyclic cannabinoids (Compton et al., 1993), indole-derived cannabinoids (Wiley et al., 1998), and anandamides (Ryan et al., 1997; Seltzman et al., 1997). In the tricyclic and bicyclic series, a 1', 1'-dimethylheptyl side chain is optimal (Compton et al., 1993) and is contained in most of the resorcinols presented here. Reducing the length of this substituent to 1', 1'-dimethylbutyl (0-1532 and 0-1890) or methyl (0- 2139) or a hydrogen (0-2010) resulted in a concomitant elimination or decrease in CB1 receptor recognition, as occurs in other cannabinoid series with similar structural manipulations (see references above).

Other structural features affecting CB1 receptor recognition and activation in this resorcinol series are related to the size, saturation, substitution, and methylation of the second, non-resorcinol ring of these bicyclic cannabinoids. In most tricyclic and bicyclic cannabinoids, the ring corresponding to the non- resorcinol ring in the current series is a cyclohexane. Reducing this size to a cyclopentane decreases CB1 affinity and potency whereas increasing it to a cycloheptane has little effect. Substitution of an adamantyl results in better CB affinity; however, potency is decreased. Similar modifications of tricyclic and bicyclic cannabinoids have not been reported. The degree of saturation of the cyclohexane ring, however, has been manipulated in several cannabinoid classes.

In the resorcinol series, the presence of a cyclohexane ring appeared optimal, although a thorough investigation of this issue was not undertaken. Introduction of a single double bond (0-1423) within the ring decreased CBi affinity and potency to the same extent as did a reduction in the size of the ring to a cyclopentane.

Hence, most structural manipulations were performed upon a bicyclic resorcinol- cyclohexane template. Degree of saturation of, as well as the position of the

double bond in the cyclohexane ring of tricyclic and bicyclic cannabinoids and in the polyolefin loop of the anandamides, has also been shown to affect CB, receptor recognition and activity in these cannabinoid classes. Greatest affinity and potency within the anandamides is achieved with four double bonds, with greater or lesser saturation resulting in a reduction in CB1 binding and/or in vivo activity (Adams et al., 1995; Sheskin et al., 1997; Thomas et al., 1996). Similarly, number and position of double bonds within the cyclohexane ring of tetrahydrocannabinols and bicyclic cannabinoids affect activity. For example, moving the double bond of A9-THC to position 8 (as in A8-THC) decreases CB affinity three-fold and somewhat reduces potency (Compton et al., 1993).

Unsaturation of the cyclohexane ring results in cannabinol with its greatly reduced CB1 affinity (Showalter et al., 1996). In contrast, CP 55,940, with a completely saturated cyclohexane ring, is several fold more potent than A8-THC-DMH which has a single double bond in the cyclohexane ring, but A8-THC with its single double bond binds with better CB1 affinity than does A9 (11)-THC which has a completely saturated cyclohexane ring (Compton et al., 1993).

The most remarkable structural features of the resorcinol series affecting CB1 affinity, however, are the length of the lipophilic side chain at position 5 and the size of the cyclic ring substituent at position 2 of the resorcinol core. THC and CP 55,940 contain two oxygens: one as a phenol (one hydroxyl in the aromatic ring) with a second oxygen incorporated into a separate ring (pyran oxygen in THC) or a hydroxyl group attached as a substituent in the cyclohexane ring as in CP 55,940. Previous research has shown that eliminating the phenolic hydroxyl of A8-THC-like cannabinoids results in deoxy-THC analogs that are CB2-selective (Huffman et al., 1999). Although some of these deoxy-THC analogs also retain reasonable affinity for CB1 receptors, orientation of their binding to CBi receptors may be inverted such that the pyran oxygen substitutes for the absent phenolic hydroxyl in hydrogen bonding (Huffman et al., 1996). In the absence of a pyran

oxygen, as in the resorcinols, the nature of the substituent at position 2 of the resorcinol core is important to maintain adequate CB1 affinity for in vivo activity.

An acyclic ring was found to be better than a heterocyclic ring with a cyclohexane ring being optimal for in vivo activity. In addition, the size and the position of the substituent on the cyclic ring is important to maintenance of CB1 affinity. The presence of a methyl substituent at position 3 enhanced activity in some cases.

Further, the 3R analog (0-1826 ; Table 2) has a poorer CB1 binding affinity (Kj = 40 nM) compared to the diastereomeric mixture 0-1657 (Kj = 14 nM; Table 2), suggesting that CB1 binding affinity is enhanced when the orientation of the methyl substituent at position 3 in the cyclohexane ring is 3S compared to 3R.

Methylation of the phenols of the resorcinols drastically decreased or eliminated CB1 affinity, perhaps because hydrogen donation is less likely from a methoxy group than from THC's free hydroxyl group (B. R. Martin, unpublished observations). Similarly, methoxy substitution for the phenolic hydroxyl in the methyl esters of A8 and A9 (11)-THC-DMH resulted in analogs that were CB2- selective and had little affinity for CB1 receptors (Gareau et al., 1996; Huffman et al., 1999; Ross et al., 1999).

Notably, with the exception of a few compounds, the dimethoxyresorcinols tested here were CB2-selective. Most of the structural features that affected recognition at CB1 receptors also affected CB2 receptor recognition, although not always to the same degree or in the same manner. These factors included length and branching of the side chain and size and degree of saturation of the non- resorcinol cyclohexane ring. In a SAR study on a series of CB2-selective deoxy- A8-THC analogs, Huffman et al. (1999) reported that length and branching of the C3 side chain affected CB2 binding in a manner similar to its effect on CB, affinity, as it did in the present study; however, the range of chain lengths for which moderate to good CB2 affinity was retained for the deoxy-A8-THC analogs was greater than the range for CB1 affinity. Similar results were obtained with a series

of CB2-selective indole-derived cannabinoids in which length of the nitrogen substituent was varied (Aung et al., 2000). To date, anandamide analogs appear to be CB1-selective with relatively little affinity for CB2 receptors across several types of manipulations (Showalter et al., 1996). Insufficient research is available to determine the effect of substitution on a cyclohexane ring on CB2 affinity across cannabinoid classes.

Other structural manipulations eliminated or drastically reduced CBi receptor recognition, but did not necessarily alter CB2 receptor binding in an identical manner. As mentioned, CB2 selectivity was most evident in the dimethoxy analogs, primarily as a consequence of severe reductions in CB affinity. HU-308, the most selective CB2 agonist to date, has a dimethoxy resorcinol core structure and does not bind to CB1 receptors at all (Hanu_ et al., 1999). In addition, greater tolerance in CB2 (vs. CB1) receptor recognition was observed with other C2 substitutions in the resorcinols. Huffman et al. (2001) recently reported that bicyclic pyridone analogs with carbonyl substitution at C1 and a nitrogen substituent substitution at C2 of THC had little affinity for CB receptors. In contrast, moderate CB2 affinity (Ki-53 nM) was retained.

Differences in allosteric regulation of CB1 and CB2 receptors by ions and guanine nucleotides has been noted previously (Showalter et al., 1996). Together, results presented here and elsewhere (see above) suggest incomplete overlap of the pharmacophores for CB1 and CB2 receptors.

In summary, structure-activity relationships of the resorcinol series presented here are consistent with the CB1 and CB2 pharmacophores of other cannabinoid classes, including tetrahydrocannabinols, bicyclic cannabinoids, aminoalkylindoles, and anandamides. In this series of resorcinols, several structural features were essential for maintenance of CB1 receptor recognition and in vivo activity, including the presence of a branched lipophilic side chain (DMH) at C5, the presence of free phenols, and substitution of a cyclohexane ring at C2. An

important structural feature for receptor recognition at CB2 receptors was side chain length, as reduction of the chain length to a methyl eliminated CB2 binding affinity. The CB2 selectivity observed with some resorcinols was maximized in the dimethoxyresorcinol analogs and this selectivity was greatly enhanced when a tertiary hydroxyl group was present in the cyclohexane ring in the same position at which the resorcinol core is attached. In contrast, the presence of unsaturation or a ketone group or an additional hydroxyl substitution in the cyclohexane ring adversely affected the CB2 selectivity. Methyl ethers were optimal for CB2 selectivity since ethyl ethers reduced selectivity.

In conclusion, although resorcinol derivatives with cyclic ring substituents at C2 are closely related to the nonactive cannabinoid cannabidiol, many of these analogs have high CB1 and/or CB2 binding affinity as well as potent in vivo activity.

In addition, because dimethoxyresorcinols are CB2 selective, they have potential to offer insight into similarities and differences between requirements for receptor recognition at CB1 versus CB2 receptors. One such difference noted here was the greater tolerance found for substitution at position 2, in the resorcinol series, for CB2 receptor recognition compared to that for CB1 receptors. The results presented here suggest that the resorcinol series represent a novel template for the development of CB1 and CB2 selective cannabinoid agonists.

While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

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Table 1. CB, and CB2 Binding Affinities and Pharmacological Effects of Phenols Ki fn : I) ED ID R R1 CB, CB. CB,/CB, SA TF RT 1 O-1376 CH, DbLH 33 = 4 3 O. a 1 85 (5-16) (3-10) (1-5) o O-153 CH3 DOt-botyl 876418 113+ 32to 7% *04 (30) (30) (30) 3 0-1601 CE120H DMH 5 0_6 3 0. 4 2 1. 1 (0. S- (0. X-1. 4) (L-2J 1 4) The Ki's are presanted as means t SEM. All ED50's are expressed as µmol/kg (with 95% confidence limits in parentheses). For compounds that failed to produce either maximal or dose-related effects, the percent effect at the highest dose (mg/kg. in parenthesis) is provided. SA = suppression of spontancous activity; MPE - % maximum possible antinociceptive effect in tail flick assay; RT = rectal temperature. DMH=dimethylheptyl. Table 2 : Pharmacological Effects and Cannabinaid Receptor Binding Affinities of Bicyclic Resorcinols K. (oM) CB/ED,. ID R Ri R2 CB, CB, CB.. S TF 0-1424 ( DMH H 9Si6 70. 4 14 27 13 13 (13-56) (9-23) (10-20) 0-1423 Yj D H n=2 1JO. I 7 O. I 0. 6 0. 6 v (0. 02-0. 6) (0-1. (0 5-0 Oz 6 t DOiH H 18 +1 2_0. 2 9 0. 6 (o. s7. 0) (0-9-1-5) (0. 1-8. C ; I660 a D M H H 7'I 3408 2 35 2. 4 4. 6 ,. _ (î. 2-3. 8) (1. 9-3. 0) (2. 4-9. 0-1425 J DMH H 15317 122 13 17 15 13 (10-29) (10-24) (10-19) 0-1661 s DMH H 138 4 28 t 12 5 24 14 24 - (13-42) (9-20) (17-34) CHj 0-1662 M DMH H >10, 000 S424U03-87% 30%-3 (; 0) 00) (30) 0-1423 a DN5H F 8l < ; 12 9 9 (8-20) (7-13) (6-15) 0-2010 f1 H C, H. j 93I. 5332 NT--18% 9%-o. 4 (; 0) (30) (30) The Ki's are presented as means ~ SEM. All ED50's are expressed as µmol/kg (with 95% confidence limits in parenrheses). For compounds dsat tailed to produce either maximal or dose-relared effects, the percent effect arthe highest dose (mg/kg; in parenthesis) is provided. SA = suppression of sponceneous activity: MPE = % maximum possible antinociceptive effect in tail fuck assay : RT - rectal temperature. Table 3 : In'Virro and rn Vivo Cannabinoid Effects ofbicyclic Resorcinols wirh Merhylated Cyclohexane K (nM) CB,/ED5" ID R Rl CB, CB, CB, SA TF RT 0-1658 1,. DMH 16 2 1 -03 16 0. 3 0. 3 (0. 1-0. 3) (0. 2-0. 35 (0. 27-0. 5 < 0-1639 . l, DMH 451 50. 9 9 48 3. 9 3-3 (3-9) (3-6) (2-5) Ph Ph 0-1663 a D M H 144+22 9+2 ló 32% 7So-. 2 (30) (30) (30) O-1657 DMR 14 0. 5 0. 8 0. 04 17 03 0. 6 0. 9 rw. y (0. 3-0. 5) (0. 5-1) (0. 7-1. 1) 0. JL DMH 50. 6 0. 40. 03 12 0. 5 1. 1 0. 7 1797A (0. 4-0. 6) (0. S- (Q. 6-1. 0) 0-Jl DhGH 4*0. 6 0. 30. 07 8 0. 2 1. 0 0. 6 I98B (0. 03-12) (0. 7-1. (0_5-0. ?) O-I826 a DNDH 40+11 Q. 8 +005 50 2. 7 2. 4 3. 6 (2. 1-3. 9) (1. 8-3. 3) (2. 7~45} 0-1890 I. JL DM-964 I3I 7 69 48 72 butyl (S5-90) 69) (46-1 If O-7571 DMH 20. 3 0. 3=0. 01 7 <1. 0' 2. 3 lj (2. 0-2. 6) (0. 3-4. 3) *This dose (µmol/kg) produced > 50% inhibition and was the lowest dose tested, The Ki's are presented as means SEM. All ED50's are expressed as µmol/kg (with 95% confidence limits in parentheses). For compounds that failed to produce either maximal or dose-related effecs, the percent effect ac the highest dose (mg : in parenthesis) is provided. $A = suppression of sponraneous activity; MPE = % maximum possible antinociceptive effect in tail flick assay : RT = recul temperature.

Table 4: CB1 and CB2 Binding Affinittes of Dimethoxy-Dimethylheptyl Resorcinal Analags K (nbl) CH7, OH C R ZZ HU 308a 10, 000 23 4-- L1J. 23 0-1999 >10, 000 23 1 4 _ 23 0 1999 ß >1 01OUO « 6 + 1 10- 24 0-1964 >10, 000 9I I 116--- 2i 0wl965 C 10, 000 >10, 000 26 0-1962 9"oL0, 000 342+22 on 27 0-2092 C°ovCX 4531 1 312 126f 12 36 28 0-2122) 3738 i lS4] 065d 7 4 29 0-2114 14 8442954 1773 1S4 3 30 O-: S/'^173 346^49 13 31 0-2123 731 t I17 I25 14 1 *The Ki's are presented as means = SEM.

'Values from Hanu_et al_ 1999. Note: Binding ligand. [1H]HU-243, was different from that used in present study.

Table 5: CB1 and CB2 Binding Affinities of Hydroxylated Dimethoxy-Dimethylheptyl Resorcinols .. K (ntW IDRRl MCBjCB, CB./CI t 32 0-207 kj (''" OCH DMH 5S2Q662 519 55 33 0-l966A aM OCHO IDMH 5055+984 23+2. 1 220 34 0967B A'"'OCH. i DMH 17l6105 HliS ! 5 ou 3 0-212 jEl. OCH. DMH 199077 101114 20 wu 36 0-2116A H OCH, 1 ? bIH 3932 483 190 17 1 37 0-2117B GDU OCH3 DO1H >10a000 1561 70- 38 0-2068 a"OCH, DNFH 7515 721 16124 47 39 0-2139 4a*'OCH, CH, >10, 000 >10, 000- 40 0-2090 a"H OC, H5 DMH 8810+-422 858 43 10 41 0-2091 a, OCH9 DMH 3201 141 6S 50 The Ki's are presented as means ~ SEM. A C D I J K I. M N I RAZDAN _, _ __..--__L-STRUCTdIRE CBl KI CB2IiI S. A. T. F. R. T. Publication (uM) (nM) EU50 (m) ur Yo effect at dose 0-1376 = 3-1', 1'-Dimethylheptyl-6- (2-isopropyl-5-methylphenyl) ph nol 3 O-1376 32. 74. 0 2. 630. 36 2. 944 1. 97 0. 822 Wiley et ai. (in press) H 0-1422 = Cyclohexyl-5- (1', 1'- dimethylheptyl)-resorcinol 4 O-1422 HO 33t2 t. 460. t 0. 3794 0. 2412 0. 19394 Wiley et al. (in press) I H 0-1423 = 2- (Cyclohex-1'-enyl)-5- (1', 1'- dimethylheptyl-resorcinol 5 O-1423 HO'u v W 96. 45t5 27. 62t5. t3 3. 918 2. 856 2. 944 Wiley et al. (in press) ?" 0-1424 = 2- (Cyclopentyl) dimethylheptyl-resorcinol 6 0-1424 HO 94. 88 : t6 6. 660. 43 8. 294 4. 481 4. 239 Wiley eí al. (ill prcss) H 0-1425=2- (4'-Tetrahydrothiopyranyl)-5- (1', 1'- dimethylheptyl-resotcinol 7 O-1425 Ho 152. 84t17 12. ISt2. 09 5. 819 5. 049 4. 526 Wiley et ul. (in prnss) H 3-1', 1'-Dimethylbutyi-6- (2-isopropyl-5-methyl- 8 0-1532 phanyl)-phenol 87618. 45 112. 6+21 Wiley er al. (ill press) H20H 3-1', 1'-Dimethylheptyl-6- (2-isopropyl-5-hydroxy-ß melltylphenyl) phenol _i-_ 4. 82t0. 56 2. 91t0. 43 _ Wilayeeul. (inpress) H (-)-4- (3, 3, 4-trans-p-Menlhadien- -\ 66°. 6 stim. 10 0-1602 (1, 6)-yi-orcinot OH > 10, 00 () > 10, 000 2-Cycloheptyl-5- (i', 1'-dimathyl- H _------ heptyl)-resorcinol 1 I O-1656 ti0 ll 0-1656 HO} + 178+1. 4 2. 12_0. 25 0. 53 0. 39 0. 21 Wileyetai (hlpress) 2- (3-Malhylcyclohexyp-5- (1', H t'-dimelhylheptyl)-tesorcinol holz ) 4. tO. 53 0. 82 : tO. 04 0. 13 0. 23 0. 29 Wiley et al. (in press) 2-(2-Methylcyclohexyl)-5-i 9H (t', t'-dimethylheptyl)-resorcinol 9 2- (4-Melhylcyclohexyl)-5- (1', 1'- vi __ __ __.. _. _____ _ _-_-- 2- (4-Mehyicyc) oh6xy))-5- (T. T- \)','" 2-(4-Methylcyclollexyl)-5-(1', 1'-> OH dimethylheptyl)-resorcinol v \ 0 t4 () tt59 HOw 45221152 473+t ? lJ4 165 135 1 12 Wileyelal. (illllles A C D I J K I. M N _ RAZDAN STRUCTURE CBl KI CB2 KI S. A. T. E. R. T. PuLltcation (M) (nn'1) ED50 (m/k) ur 96 effect at Juse 2-(2-Adamantanyl)-5-(1', 1'-di-inl methyiheptyl)-resorcinol i IS O-1660 Ho 7. St1. 2 3. t60. 8t t. 273 0. 911 1. 729 Wile etul. (in ress) 2- (Tetrahydrolhiophen-3-yl) tt - 5- (t', 1'-dimethylheptyl)-re- sorcinol 16 O-1661 H 138t3. 7 27. 7tl2. 1 7. 648 4. 389 7. 781 Wiley et al. (in press) 2- (1-Methylpiperidin-4-yl)- 5- (1', 1'-dimethylheptyl)-re- sorcinol i 7796 stim 1 @ 10. L. eAal 17 7 0-1 662 HO 2 >10, 000 5424tII03 @IU 7@10 @30 Wile ct : d. (in ress) 2- (4-Phenylcyclohexyl)- 5-(1', 1'-dimethylhoptyl)- résorcinol ur>X 18 0-1663 143. 7t21. 9 8. 8t1. 6 3296@30 796@30 mg2. 2°H30 Wile ttat. (in ress) 2- (3-Methylcyclohexyl)-5- H (1', 1'-dimethylheptyl-resorcinol isomer A))) 0. 25H20 Hcr\< ! 9 O-1797 5. 21t0. 57 0. 440. 03 0. S4 MM 0. 252 Wiley et at. (in press) 2- (3-Methylcyclohexyl)-5- H (1', 1'-dimethylheptyl)-resorcinol isomer B H 20 O-1798 4. 33 t 0. 58 0. 48t0p7 0. 070 0. 379 0. 2J8 Wifeyetitt. (in press) (-)-2- (3-3, 4-Irans-p-menthadien- (1, 8)-yl)-orcinol i Xt 21 O-1821 H> >IO, OOt7 0@30 8@30 ne I@30 2-(3R-Methylcyclohexyl)-tAt QH 5- (1', 1'-dimethylheptyl) resorcinol i 22 ()-18 ? 6 H 40 t 10. 9 0. 8 t 0. 05 0. 915 0. 821 1. 162 Wiley el al. (ill menLhachon- (I, B)-yi)- menhaden- (1, 8)-yl)- oH resocind 49 > t0, 000 í-J-4-13-3, 4-uans p-1 munlhadiam (1, B) yl)- oasocinW i 24 0-1848 O H >IO. OOO (-)-2- (3-3, 4-trans-p-mentha- then (1. 8)) yl)-4. 6-dnodoorcinol > eC H 2S O 808 _. o t >lO, OiiO. _ _ _ 2- (3, 3-Dimethylcyclohexyl-5- (1', 1'- OH dimethylheptyl)-resorcinol HO' 2G O-1871 H 2. 3i032 0. 3i001 0. 0 0. 7 0. 37 ACD ! J K L MN I KAZUAN STRUCTURE CBlKt CBZKt S. A. T. F. R. T. Publicaliou 2 Otl (nM) (nM) Eu50 (m) or'£ effect at dose 2- (3-Mothylcyclohexyl)-5- (I', I'- H dimethylbulyl)-resorcinol 27 0-89o Ho -- 96. 1 *3. 53 I3. 2t1. 4 20 14 21 2-CyGohexyl-5-mehyl-resacind H 1 28 0-1917 _ (-)-I, 3-Dim3rhoxy-2-(3-3*4-trans-1 p-menthadion- (1, 8)-yi)-orcinol ctH, i i 2910-1918 1 (-)-2- (3-3. 4-trans-p-menthadien- (1, 8jyl)-monomethwry ocinol cH YN 30 O- (9t9 0 Ha 0-1962 H CH3 4-14- (I, I-Drnathyl-heptyl)-2, 6-di- melhoxy-phenyl)-tevahydropyran-4-d, 3l O-1962 H >I0, 000 342*22. 4 36% @30 23% @30 neg0. 9@30 Witey etui. (in press) 0-1964 4-14- (I, I-Dimethyl-heptyl)-2. 6- dimethoxy-phenyl] telrahydro- i 32 o-1964 pyran >10, 000 91 li-I 16 negi. 9@30 30% @30 negO. 6@30 Wileyetal. (inpress) 0-1965 (O qcti3 4- [4- (I. I-Ditnothyl-heptyl)-2, 6- dnmethoxy-phenylJ-3, 6-dnhydro-2H-pyran 33 0. 965 H'°° , >10, 000 >10, 000 WileyCt : ll. (inpress) 01966 H CH3 - (4-f. t-oimemyl. hepvyy-2, 6-dimothoxy-phenylj, 3methyl- \ cyclohexanoi isomer 1/ 34 O-t9b6_-H' SOSSt983. 8 23 t 2. 1 ne I9. 0@3 5. 1 @30 0. 5@30 Wiley a al. (in press) nag 1- [4 (t, t-Dimethyl-heptyl-2, 6-dimelhoxy phenytj 3-methyl-~ { cyclohexanol isomer 2 35 0-1907_ 3/\ 1716. 3tIW. 8 Llit7. 8 42. 9@30 8. 2@30 0@30 Wileyeal. (in ress) 0-1999 CH, - ( I-Difnethyl-heplyl). 1, 3- (tmethoxy-2- (3-methyl-cyclo- hexyl)-benzene/ 36 O-I99' 30 0-1999 > 10, 000 465. 6t 110 4@30 6@30 IV30 Wiley et ul. (in press) 02010 2-Cyclohexyl-4 hexyl resorcinoi @rC6H 6H 13 H 37 U- ? 010 9515t332. 5 ne 17. 79@3 9. ORu@30 ne 0. 4@30 Wile e al. (in press) 0-206S 1 DHdCH3 1 l4 (1, 1 Dlmelhylheplyl) 2, 6 dimelhoxy v phunyll 3, 3-dimnyyl cyclohexanol 3ii 17268 H'O 7515t720. 9 l61.-i8f2. t. 31 Wile et al. (in ress) A C D I 1 K I. M N 1 RAZDAN-__ -_^_--_-__-4_ STRIICTdJRE-CBl KI CB2 KI S. A. T. F. R. T. Publicatiou 2 0# (IIM) (IIM) ED50 (tug/kg) or % effect at dose 0-2072 H C H 1- [4-1, 1,-Dimethylheptl)-2. 6-dimethox phenylj cyciohexanol 1i 1 v 39 O-2072 oH2 582033*66231 10536t18. b6 Wile etal. (in press) O-2090 H Et 1- [4- (1, 1-Dimethylheptyl)-2, 6-dietl phenyl]-3-methyl cyclohexane-1-o EtOz A 40 0-2090 8809. 67422. 15 857. 67t42. 9 press) Et0 Wilo et uI. (in ross) 0-2091 H Me 1- [4- (I, I-Dimethylheptyl)-2, 6-dimt phenyl]-cycloheptan-1-ol M eOw ~ 41 O-3091 3200. 67t141. 0-t 63. 83t8. 21 M e0 Wile et xl. (in ress) 0-2092 OH 8- [4- (1, 1-Dimelhylheptyl)-2, 6-dim pheny-1, 4-dioxaspiro [4. 5] decan- 42 O-2092 458133t3I1. 65 125. 53t12. 45 M e0' Wile et al. (in ress) <- [4yt, 1-Dimethyl-hePMI-26- dimelhoxy-phenylJcyclohex-3-CH, annone 43 zlla 8441. 7t9543 I772. 7t183. 7 Wiley et al. (in ress) A- [5- (1. 1-Dimettyl-heptyl)-2. 6- dunohoxy-phylJ-0-hyckoxy-H CH cyclohexans 44 2i t5 _ _ __ _ _ H, Ce 4571. 7173. 4 345, 7i48 8 _ _ _ Wiley a al. (ill press) 4a ? I. IS 4571. 7t173. 4 345. 7t48. 8 Y P H, CO'-\% e Wile ec al. (iu ress) 1- (4- ( t. t-Ounethylhepyl)-2. 6- dunohoxy-phmylJcycbhexane-H Ha 1 4-diol () 5 2116 H C Wiley et al. (in press) 1- (4- (t. t-Dimathyl-hapH)-2, 6- _ 3931. 7*d83. 4 190. 3* (7. 0 duuhoxyphonyl/cyclohaxane-H H,.. _. 1 44id (B) t4M (6)"-' Wiley et al. (iu ressl Name d slrucW e notprven, HzOH also structure needs an arrow Resently its drawn wilh MW lor-CH, mJa C22H3003, should be C24H3203 47 2118 64413t1389. 5 3352t253. 2 _ pen, stpl3syi5nSYi W/ 40 2121-Hco l9JOt76. 66 100. 6713. 88 Wiley et al. (ill press) 6 j4- (t. t Dimethyl-hepry)-2 6--- dwnehoxy phenylJ-7-oxa-d4 : yclo Ha [4 1 Ohnptan-31 H CC ? 49 1122 Wiley et ul. (iu press) 3 (A- (1, 1-Dimehyl-heqyl)-2. 6-. d3mrshoxy phenylj-3-hydroxy-S Jk methyl-cyclohoxanone H cH, 50 >123 e, co- 1730. 67t116. 8G 12t. J3i13 d0 Wileyetal. (in ress) A D K L M N I RAZDAN STRLJCTdIRE C81 KI CB2 KI S. A. T. F. 2 « h1) OM) ED50 pu/Ic) or 96 effect at duse 0-2137 CH3.. _ 1 J4- (I, l dim ihaxy-phanyll-3 otho- cyclohaxanol 51 2137__-_-H- 2665i1a5. 31 II. Ot2. 18 0-2139) CH, 0 2139 1 (2. 6 Dumethoxy-0-molhyl- plxinyi)-3, 3-dimehylcyclo- hexanol 52 213) 3 _ >10, 000 >l0, 000 Wileyet al. (inpress) Cl, 1- (2, 6-D melhoxy-4-methyl- phenylj-cyclohexanol 53 O-2398---HCO CH3 >lO, OIKI >10, 000 CH, 2-Cycbhexyl-1, 3-dimethoxy-5- mettylbenzene $-1 O-2299 H, CO H, >10. >10, 000