Patent Number: 6,169,178

Title: Process for the preparation of 16,17 acetals of pregnane derivatives with control of the epimeric distribution at the C-22 position

Abstract: Described herein is a process for the preparation of an acetal of formula (I) in which R.sub.1 is an alkyl, R.sub.2 is H or an acyl, X is .beta.-OH and Y is H, comprising the acetalization with control of the epimeric distribution at the C-22 position, for treatment with R.sub.1 CHO in aqueous HBr or HI of a compound of formula (II) in which R.sub.2 has the meaning specified above, R.sub.3 and R.sub.4 are both H, or, taken together, are --C(R.sub.5)(R.sub.6)--, where R.sub.5 and R.sub.6, which may be the same or different from one another, are alkyl groups, and X and Y are chosen from among the following: A) X and Y, taken together, are an additional bond between C-9 and C-11; B) X is .beta.-OH, and Y is H or an .alpha.-halogen; C) X is .beta.-OR.sub.7 where R.sub.7 is an acyl, and Y is H or an .alpha.-halogen; and D) X and Y, taken together, are --O--.

Inventors: La Loggia; Filippo (Gropello Cairou, IT), Petacchi; Paolo (Paullo, IT)

Assignee: Farmabios S.r.l.

International Classification: C07J 71/00 (20060101); C07J 071/00 ()

Expiration Date: 01/02/2018