Synthesis and biological evaluation of 9-(5′,5′-difluoro-5′-phosphonopentyl)guanine derivatives for PNP-inhibitors
摘要:
9-(5',5'-Difluoro-5'-phosphonopentyl)guanine (DFPP-G) and its hypoxanthine analogue (DFPP-H) were modified by introducing a methyl group to all possible positions of the linker connecting a purine and difluoromethylenephosphonic acid moiety to evaluate the effects of the methyl group on inhibition against purine nucleoside phosphorylase. The methyl group on the linker affected the inhibition in a positional-dependent manner. Inhibitory potency of alpha-methyl and beta-methyl -substituted analogues of DFPP-H increased by about 600- to 1000-fold upon converting to cyclopropane nucleotide analogue (+/-)-4. (c) 2005 Elsevier Ltd. All rights reserved.
Sphingolipids and Glycerolipids. Part II. Syntheses of Two Pairs of Enantiomeric C18-Sphingosines and a Palmitoyl Analogue of Gaucher Spleen Glucocerebroside.
Palladium complexes catalyze the 1,4-addition of acetic acid to butadienemonoxide to give 4-hydroxybut-2-en-1-yl acetate. The highest 1,4-/1,2-addition selectivity of 18.9 was achieved. The reaction seems to proceed via a Wacker-like mechanism.