George Detre

Synthesis of (+)-8a,9-secoartemisinin and related analogs

Abstract An efficient synthesis of (+)-8a,9-secoartemisinin 2 , ring-D cleaved, tricyclic analog of (+)-artemisinin 1 , has been accomplished. Dioxetane 7 , produced upon ozonolysis of vinyl-silane 5 in methanol, was intercepted with acid to provide the stable bicyclic peroxy-aldehyde 9 , which was readily converted to the title compound(s).

Synthesis and testing of 17aβ-hydroxy-7α-methyl-d-homoestra-4, 16-dien-3-one: a highly potent orally active androgen

Abstract The title compound, 17aβ-hydroxy-7α-methyl- d -homoestra-4, 16-dien-3-one (3), was synthesized in five steps (17% overall yield) from 7α-methylestrone methyl ether (5) and was found to possess oral androgenic activity, in excess of other known androgens, without using 17α-alkyl substitution. (Steroids 55 :59–64, 1990)

Semisynthetic aminoglycoside antibacterials. Part II. Synthesis of gentamicin X2 and related compounds

Gentamicin X2, naturally occurring aminoglycoside antibiotic produced as a minor component together with the clinically important gentamicin C complex by Micromonospora purpurea, has been synthesized by glycosylation of suitably protected garamine derivatives. The synthesis of the α-glycoside was accomplished by means of the Lemieux–Nagabhushan reaction as well as by using a Koenigs–Knorr reaction. The latter reaction was also used to prepare 4-O-β-analogue of gentamicin X2. The syntheses of other analogues of gentamicin X2, namely 4-O-[2-amino-2-deoxy-α-D-mannopyranosyl], 4-O-[2-amino-2-deoxy-α-D-galactopyranosyl], 4-O-[2-amino-2-deoxy-α- and -β-D-glucofuranosyl], 4′-O-[2-amino-2-deoxy-α-D-glucopyranosyl], 4-O-α-D-glucopyranosyl, 4-O-α-D-talopyranosyl, and 4-O-2-deoxy-α-D-galactopyranosyl derivatives of garamine, are also described.

Semisynthetic aminoglycoside antibacterials. Part V. Synthesis of pentosyl and related derivatives of garamine

The application of the Koenigs–Knorr and Lemieux–Nagabhushan reactions to the synthesis of a variety of novel 4-O-pentofuranosyl and 4-O-pentopyranosyl derivatives of garamine is described. The solution conformations of these novel pentosyl aminocyclitols have been assigned on the basis of 13C n.m.r. data.