Scott Alan Frank

Selective estrogen receptor modulators

Selective estrogen receptor modulators (SERMs) are structurally diverse compounds that bind to estrogen receptors (ER) and elicit agonist or antagonist responses depending on the target tissue and hormonal milieu. They are being evaluated primarily for conditions associated with aging, including hormone-responsive cancer, osteoporosis and cardiovascular disease. Several SERMs are marketed or are in clinical development, including triphenylethylenes (tamoxifen and its derivatives: toremifene, droloxifene and idoxifene), chromans (levormeloxifene), benzothiophenes (raloxifene, LY353381) and naphthalenes (CP336,156). Tamoxifen and toremifene, both used to treat advanced breast cancer, also have beneficial effects on bone mineral density and serum lipids in postmenopausal women. Tamoxifen was recently shown to decrease the risk of invasive breast cancer in women at high risk. Unfortunately, both drugs also have stimulatory effects on the endometrium. Raloxifene, used for prevention of postmenopausal osteoporosis and fragility fractures, also has favourable effects on bone mineral density, serum lipids and the incidence of invasive breast cancer in postmenopausal women but does not stimulate the endometrium. Like replacement estrogens, SERMs increase the risk of venous thromboembolism. SERMs offer postmenopausal women many of the advantages of estrogen replacement while mitigating some of the disadvantages, particularly the concern over breast cancer. Newer SERMs, exemplified by raloxifene, also eliminate the concerns over endometrial stimulation that were not addressed by first generation SERMs. The clinical success of SERMs has set the stage for a variety of drug therapies based on selective modulation of nuclear receptor activity.

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.

Design, synthesis and structure-activity-relationship of 1,5-tetrahydronaphthyridines as CETP inhibitors.

This Letter describes the discovery and SAR optimization of 1,5-tetrahydronaphthyridines, a new class of potent CETP inhibitors. The effort led to the identification of 21b and 21d with in vitro human plasma CETP inhibitory activity in the nanomolar range (IC(50)=23 and 22nM, respectively). Both 21b and 21d exhibited robust HDL-c increase in hCETP/hApoA1 dual heterozygous mice model.

STUDIES ON THE PHOSPHORYLATION OF LY303366

Abstract Phosphorylation of LY303366 ( 1 ) was studied in THF and DMF. Benzyl phosphate 2 could be prepared in excellent yield using LiOH as the base. Both 2 and the derived phosphonic acid monosodium salt 3 were prone to undergo hydrolytic dephosphorylation.