The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 27, 1996
Filed:
May. 04, 1995
Bio-Mega/Boehringer Ingelheim Research, Inc., Laval, CA;
Abstract
Disclosed herein is a stereospecific synthesis amenable to the large scale preparation of a hydrochloric acid addition salt of a chlorohydrin of the formula ##STR1## wherein R.sup.1 and R.sup.2 are amino protective groups and R.sup.3 is an amino acid side chain or a protected amino acid side chain. The synthesis involves reacting an aldehyde of the formula ##STR2## wherein R.sup.1, R.sup.2 and R.sup.3 are as defined hereinbefore with (chloromethyl)lithium at -20.degree. C. or below and contacting the resulting diastereoisomeric mixture of lithium alcoholates with aqueous hydrochloric acid to obtain a separable mixture of the hydrochloric acid addition salts of the chlorohydrin and its corresponding hydroxy diastereoisomer. The hydrochloric acid addition salt of the chlorohydrin is transformed readily into corresponding optionally amino-protected aminoepoxides; for example, 3(S)-(tert-butyloxycarbonylamino)-l,2(S)-epoxy-4-phenyl-butane.