Dongkook Pharmaceutical Co., Ltd.

Hee Sock Park

Jin Kyu Park

Yong Hae Kim

Kwon Kim

Yong Hyun Kim

Dong H Lee

The object of this invention is to provide novel buprenorphine analgesic analogues represented by following formula(I) and their non-toxic pharmaceutically acceptable salts. ##STR1## wherein R.sub.1 is hydrogen atom, methyl, ethyl, cyclopropyl or cyclobutyl; and

Buprenorphine analgesic analogues

The object of the present invention is to provide an improved process for preparing benzodiazepine-3-alkyl carboxylate of formula(I) and its pharmaceutically acceptable salts and esters. ##STR1## wherein R.sup.1 is methyl, ethyl or isopropyl;

Process for preparing benzodiazepine derivatives

This invention relates to novel processes for preparing substituted pyrrolizine compounds. More particularly, it relates to novel processes for preparing 5-aroyl-2,3-dihydro-1H-pyrrolizine-1,1-dicarboxylate of the following formula (I) from pyrrole. ##STR1##

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Taejeon, South Korea

Hee Sock Park