摘要:
The present invention relates to the manufacture of the compounds of formula (I) said compounds of formula (I) being valuable intermediates in the manufacture of Dolastatin 10 analogues, which are useful in the treatment of cancer.
摘要:
A process for the racemization of atropisomeric bis(phosphine oxide) compounds of formula I: in their (S) or (R) or non-racemic form, is useful for preparing optical active bisphosphine ligands, that form optical active complexes with transition metals. Racemization is thermal and carried out in high or low boiling solvent, under normal or elevated pressure at 105 to 3.5×107 Pa. Heating is performed in a system that allows heating up to 400° C. (reactor, autoclave, aluminum block, round-bottom flask with heating/stirring mantle and the like) or by microwave irradiation or in the melt at a temperature from 260 to 400° C.
摘要:
The invention is concerned with novel water-soluble racemic or optically active compounds of formulae ##STR1## wherein R.sup.1, R.sup.2, R.sup.3 and R.sup.4 independently signify lower alkyl or lower alkoxy;m and n are 0, 1 or 2; andX signifies hydrogen, an alkali :metal, the equivalent of an earthalkali metal or an ammonium ion;with the provision that R.sup.3 is in position 4 or 5 and R.sup.4 is in position 4' or 5'. The invention is also concerned with complexes of such compounds with a metal of Group VIII. These complexes are, useful as catalysts for asymmetric hydrogenation and for enantioselective hydrogen displacement in prochiral allylic systems.