The Nazarov cyclization, a well-known method for the formation of cyclopentenones, mechanistically involves the 4π electrocyclization of a 1,4-pentadienyl cation, generated from cross-conjugated divinyl ketones. Recently, advances related to this cyclization, such as the incorporation of heteroatoms as well as the use of cyclopropanes as double bond equivalents have extended the scope of the original reaction. The modifications discussed in this review, which covers the years 2009-2013, have allowed the realization of both heteroatom- and homo-Nazarov cyclizations.
View Article and Find Full Text PDFA novel series of pyrazolo[1,5-a]pyrimidines bearing a 3-hydroxyphenyl group at C(3) and substituted tropanes at C(7) have been identified as potent B-Raf inhibitors. Exploration of alternative functional groups as a replacement for the C(3) phenol demonstrated indazole to be an effective isostere. Several compounds possessing substituted indazole residues, such as 4e, 4p, and 4r, potently inhibited cell proliferation at submicromolar concentrations in the A375 and WM266 cell lines, and the latter two compounds also exhibited good therapeutic indices in cells.
View Article and Find Full Text PDFModification of alpha-biphenylsulfonamidocarboxylic acids led to potent and selective MMP-13 inhibitors. Compound 16 showed 100% oral bioavailability in rats and demonstrated >50% inhibition of bovine cartilage degradation at 10 ng/mL.
View Article and Find Full Text PDFThe preparation of alpha-methylbenzyl thioureas and their biological activity against varicella zoster virus is described. Several analogs demonstrated IC50s<0.1 microM and their SAR are discussed.
View Article and Find Full Text PDFA series of highly potent thiourea inhibitors of cytomegalovirus (CMV) with improved stability properties was prepared and evaluated. Compound 29 inhibited the virus in cultured HFF cells with IC50 of 0.2 nM.
View Article and Find Full Text PDFBioorg Med Chem Lett
September 2003
Bis-(aryl)thioureas were found to be potent and selective inhibitors of cytomegalovirus (CMV) in cultured HFF cells. Of these, the thiazole analogue 38 was investigated as a potential development candidate.
View Article and Find Full Text PDFCurr Opin Drug Discov Devel
September 2003
Inhibitors of matrix metalloprotease (MMP)-13 and tumor necrosis factor-alpha converting enzyme (TACE) have been highly sought as potential therapeutic agents for the treatment of osteoarthritis and rheumatoid arthritis, respectively. This review focuses on the published literature on these inhibitors from 2001 to mid-2003. Significant advances have been reported in the design and synthesis of potent and selective inhibitors of MMP-13 using hydroxamic acid and non-hydroxamate zinc chelators on a variety of scaffolds.
View Article and Find Full Text PDFThe synthesis and biological activity of pyrimidotetrazin-6-ones against HCMV protease is described. The mechanism of action for these inhibitors is the oxidation of several cysteine residues to generate cross-linked enzyme.
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