A salt of a heterocyclic azahexane compound

Abstract

There is described a salt of a compound of formula I, wherein R1 is lower alkoxycarbonyl, R2 is secondary or tertiary lower alkyl or lower alkylthio-lower alkyl, R3 is phenyl that is unsubstituted or substituted by one or more lower alkoxy radicals, or C4-C8cycloalkyl, R4 is phenyl or cyclohexyl each substituted in the 4-position by unsaturated heterocyclyl that is bonded by way of a ring carbon atom, has from 5 to 8 ring atoms, contains from 1 to 4 hetero atoms selected from nitrogen, oxygen, sulfur, sulfinyl (-SO-) and sulfonyl (-SO2-) and is unsubstituted or substituted by lower alkyl or by phenyl-lower alkyl, R5, independently of R2, has one of the meanings mentioned for R2, and R6, independently of R1, is lower alkoxycarbonyl. The salt of a compound is an inhibitor of retroviral aspartate protease and can be used, for example, in the treatment of AIDS. It exhibits outstanding pharmacodynamic properties.