Robert H. Lenhard

Steroidal cyclic ketals: The preparation of steroidalΔ4-3-ethyleneketals

Ersatz vonp-Toluolsulfosäure durch Oxal- oder, bevorzugt, Adipinsäure in Salmis Methode für die Synthese vonΔ 5-3-Äthylendioxysteroiden führt zuΔ 4-3-Äthylendioxysteroiden.

The synthesis of some 21-chloro- 16α, 17α-acetonides

Abstract The preparation of several 21-chloro-11β-hydroxy-16ga, 17α-acetonides is described. The preparation of the analogous 9α, 11β-dichloro-acetonides is also given. The thymolytic activities of these compounds are discussed and tabulated.

Derivatives of D-penicillamine as potential antiarthritic agents

Abstract A variety of synthetic molecules based on D-penicillamine was examined in the established type II collagen arthritis model in rats.

The preparation and biological activity of 9α,11β-dichloro-21-hydroxy-16α,17α-isopropylidenedioxypregna-1,4-diene-3,20-dione

The preparation of 16α,21-diacetoxy-9α,11β-dichloro-17α-hydroxypregna-1,4-diene-3,20-dione (I) and 9α,11β-dichloro-21-hydroxy-16α,17α-isopropylidenedioxypregna-1,4-diene-3,20-dione (IIa) is described. The thymolytic activities of these and other 9α,11β-dichlorocorticoids are discussed.

An unusual dehydrogenation of steroidal Δ5(10),9(11)-dienes

Abstract Dehydrogenation of a Δ5(10),9(11)-3-keto Δ5(10),9(11)-3-hydroxy-steroid with 2,3-dichloro-5,6-dicyano- p -benzoquinone afforded the corresponding Δ4,9,11-3-ketone.

AN EFFICIENT DEGRADATION OF TAZOBACTAM, A BETA-LACTAMASE INHIBITOR, TO METABOLITE M-1

Abstract An efficient preparative degradation of tazobactam [(2S,3R,5S)-3-methyl-7-oxo-3-(1H-1,2,3-triazol-1-yl-methyl)-4-thia-1-azabicyclo[3.2.0]-heptane-2-carboxylic acid 4,4-dioxide] to the metabolite M-1 [[S-(R∗,R∗)]-2-amino-3-methyl-3-sulfino-4-(1H-1,2,3-triazol-1-yl)butyric acid] without intermediacy of a chromatographic procedure is described.