Abstract: Compounds of general formula I: ##STR1## wherein: each of R.sup.1 -R.sup.8, k, and V represent disclosed functional groups that have been chosen such that all disclosed variations of compound I and their pharmaceutically and veterinarily acceptable acid addition salts and hydrates are antagonists of platelet activating factor (PAF) and as such are useful in the treatment or amelioration of various diseases or disorders mediated by PAF.

Abstract: Compounds of either of general formulae (I) and (II), wherein: R.sup.1 represents a C.sub.1-8 alkyl, C.sub.3-8 cycloalkyl, C.sub.3-8 cycloalkyl(C.sub.1-8)alkyl, C.sub.2-8 alkenyl, or C.sub.1-6 alkyl substituted phenyl group; R.sup.2 represents a C.sub.1-8 alkyl, C.sub.2-8 alkenyl, C.sub.2-8 alkynyl group or a C.sub.1-5 alkyl, C.sub.2-5 alkenyl or C.sub.2-5 alkynyl group substituted with a substituted phenyl group; R.sup.3 represents a hydrogen atom or a substituent R.sup.4 or M; R.sup.4 represents a C.sub.1-5 alkyl group, or C.sub.1-5 alkyl group substituted with a group chosen from substituted phenyl, dimethylamino and acetylamino; R.sup.5 represents a hydrogen atom or a methyl or ethyl group except that when R.sup.2 is methyl then R.sup.5 is not methyl; M represents a cation capable of forming a pharmaceutically acceptable salt; Q represents C.dbd.

Abstract: Compounds of the general formulae: ##STR1## in which Ar and Ar.sup.1 which may be the same or different represent aromatic radicals optionally substituted once or more than by substituents selected from halogen, lower alkyl and lower alkoxy and Alk represents an alkylene group containing from 1 to 4 carbon atoms which alkylene group may be interrupted with a heteroatom; and acid addition salts thereof.These compounds have anti-anaerobe and also anti-fungal activity and are non-mutagenic.