Severe distortion of π-allyl orientation in a molybdenum complex containing a sterically demanding ligand: crystal structure of hydrotrix(3,5-dimethylpyrazolyl)borato-(π-cinnamyl)-dicarbonyl molybdenum(II)

Steric interaction between terminal allyl substituent and the proximal 3-methyl group of the pyrazole can result in a severe distortion of the π-allyl orientation, as diagnosed by the downfield chemical shift of the central proton of the allyl group and confirmed by the X-ray crystal structure of a π-cinnamyl complex of molybdenum containing hydrotris-(3,5-dimethylpyrazolyl)borate ligand

Synthesis of 11β-(4-dimethylaminophenyl)-17β-hydroxy-17α-(3-methyl-1-butynyl)-4,9-estradien-3-one and 11β-(4-acetophenyl)-17β-hydroxy-17α-(3-methyl-1-butynyl)-4,9-estradien-3-one: two new analogs of mifepristone (RU-486)

From the structure activity relationship, two new analogs, 2 and 3, of the potent progesterone antagonist mifepristone 1 have been designed. The syntheses of these two analogs have been achieved in eleven steps through modified synthetic sequences and improved procedures starting from (+)-estrone. In comparison with mifepristone 1, the relative binding affinities of compound 2 for the progesterone receptor was found to be more, whereas that of compound 3 was less