Long-acting contraceptive agents: Levonorgestrel esters of unsaturated acids
摘要:
Esters of levonorgestrel (13 beta-ethyl-17 beta-ethynyl-17 beta-hydroxygon-4-en-3-one) with a variety of unsaturated carboxylic acids have been synthesized for evaluation as potential long-acting, injectable contraceptive agents.
Long-acting contraceptive agents: Levonorgestrel esters of unsaturated acids
摘要:
Esters of levonorgestrel (13 beta-ethyl-17 beta-ethynyl-17 beta-hydroxygon-4-en-3-one) with a variety of unsaturated carboxylic acids have been synthesized for evaluation as potential long-acting, injectable contraceptive agents.
1, 1'-Oxalyldiimidazole (ODI, 3) is a useful reagent for the degradation of 3-aryl-2-hydroxyiminopropionic acids (2) into the corresponding arylacetonitriles (1) under essentially neutral conditions.
noic acids (1), mostly with a furan or thiophene nucleus as a heteroaryl group, were synthesized in 48-94% yield by the reduction of 3-(heteroaryl)-2-(hydroxyimino)propanoic acids (5) with zinc dust and formic acid in the presence of a catalytic amount of iron dust at 60 degrees C for 2 h. Under these conditions, unfavorable hydrogenolysis of bromine on the thiophene nucleus does not occur. Traditional