Margaret M. Faul

Salt form selection and characterization of LY333531 mesylate monohydrate

LY333531 is a potent protein kinase C(beta) (PKC(beta)) inhibitor currently under development for the treatment of diabetic complications. Seven salts of LY333531 (hydrochloride, sulfate, mesylate, succinate, tartrate, acetate and phosphate) were evaluated during the early phase of development. Physical property screening techniques including microscopy, DSC, TGA, XRPD, hygroscopicity and solubility were utilized to narrow the selection to two salts: the mesylate and hydrochloride. Identification of the optimal salt form was based upon solubility, bioavailability, physical stability and purity. During the evaluation process three hydrated forms (anhydrate, monohydrate, and tetrahydrate) of the hydrochloride salt were identified. The mesylate salt was found to give only one, a monohydrate. Processing parameters (e.g. filtration rate, crystal form stability) demonstrated that the anhydrate was the preferred form of the hydrochloride salt. Bioavailability studies in dogs indicated that the C(max) and area under the plasma concentration vs. time curve (AUC) for LY333531 and its active metabolite, LY338522, following administration of the mesylate salt were approximately 2.6 times those obtained after the LY333531 HCl dose. This difference was presumed to be due primarily to the fact that the mesylate was five times more soluble than the hydrochloride salt in water. These factors led to selection and development of LY333531 mesylate monohydrate as the active pharmaceutical ingredient for clinical evaluation.

Acyclic N-(azacycloalkyl)bisindolylmaleimides: Isozyme selective inhibitors of PKCβ

The synthesis and structure-activity relationship (SAR) trends of a new class of N-(azacycloalkyl)bisindolylmaleimides 1, acyclic derivatives of staurosporine, is described. The representative compound for this series (1e) exhibits an IC(50) of 40-50 nM against the human PKCbeta(1) and PKCbeta(2) isozymes and selectively inhibits the PKCbeta isozymes in comparison to other PKC isozymes (alpha, gamma, delta, epsilon, lambda, and eta). The series is also kinase selective for PKC in comparison to other ATP-dependent kinases. A comparison of the PKC isozyme and kinase activity of the series is made to the kinase inhibitor staurosporine.

A new one step synthesis of maleimides by condensation of glyoxylate esters with acetamides

Bisphenyl, Bisheteroaryl, indolylaryl and indolylcycloalkyl maleimides are prepared in one step and 67–99% yield by condensation of glyoxylate esters with acetamides using a 1.0 M solution of potassium tert-butoxide in THF. The mechanism of the reaction is discussed.

Novel, potent and selective cyclin D1/CDK4 inhibitors: indolo[6,7-a]pyrrolo[3,4-c]carbazoles.

The synthesis and CDK inhibitory properties of a series of indolo[6,7-a]pyrrolo[3,4-c]carbazoles is reported. In addition to their potent CDK activity, the compounds display antiproliferative activity against two human cancer cell lines. These inhibitors also effect strong G1 arrest in these cell lines and inhibit Rb phosphorylation at Ser780 consistent with inhibition of cyclin D1/CDK4.

Aryl[a]pyrrolo[3,4-c]carbazoles as selective cyclin D1-CDK4 inhibitors

The synthesis of new analogues of Arcyriaflavin A in which one indole ring is replaced by an aryl or heteroaryl ring is described. These new series of aryl[a]pyrrolo[3,4-c]carbazoles were evaluated as inhibitors of Cyclin D1-CDK4. A potent and selective D1-CDK4 inhibitor, 7a (D1-CDK4 IC(50)=45 nM), has been identified. The potency, selectivity profile against other kinases, and structure-activity relationship (SAR) trends of this class of compounds are discussed.

PALLADIUM-CATALYZED ACYLATION OF A 1,2-DISUBSTITUTED 3-INDOLYLZINC CHLORIDE

Abstract 3-Acylindoles were prepared by pallladium catalyzed coupling of an acid sensitive 1,2-disubstituted 3-indolylzinc chloride with a number of acid chlorides to give the corresponding ketones in 33–74% yields.

Phenyliodine(III) bis(trifluoroacetate)-mediated oxidation of bisindolylmaleimides to indolo[2,3-a]carbazoles

A novel protocol for the oxidation of bisindolylmaleimides to the corresponding indolo[2,3-a]carbazoles in 15–56% yield with phenyliodine(III) bis(trifluoroacetate) (PIFA) is reported.

Synthesis of 2′,3′-dideoxy-3′-hydroxymethylcytidine; a unique antiviral nucleoside

Abstract The synthesis of 2′,3′-dideoxy-3′-hydroxymethylcytidine 1 was accomplished using two different approaches. First, uridine and cytidine were used to prepare the key intermediate epoxides 15 and 31 which were opened with cyanide, deoxygenated by elimination to vinyl nitriles 17 and 36, and reduced by 1,4 hydride addition to the saturated nitriles 18 and 37. Secondly, a novel Rh-catalyzed hydroformylation reaction of 2′,3′-didehydro-2′,3′-dideoxycytidine 46 was used to prepare 1 in four steps. The attempted use of 2′-deoxyuridine and 2′-deoxycytidine to prepare 1 is also discussed.

Synthesis of 7-cyano- and 7-acetamido-indoles via cyanocarbonation/hydrogenation of 7-formyl indole

A procedure for the synthesis of 7-cyano and 7-acetamido indoles via cyanocarbonation/hydrogenation of 7-formyl indole is presented. The process can be efficiently scaled up to provide multigram quantities of the desired compounds in good yield. A small survey of substrate scope indicates that the reaction may prove generally useful for the synthesis of aryl acetonitriles.

Synthesis of bisindolylmaleimide macrocycles

Abstract The synthesis of a novel class of N-N′-macrocyclic bisindolylmaleimides is reported. The key step involves a remarkably efficient intramolecular cyclization reaction. The method was further developed to provide an efficient synthesis of this type of macrocycle through an intermolecular alkylation with subsequent intramolecular cyclization.