Disclosed are compounds of the Formula I wherein: Z is C or nothing, provided that when Z is nothing, R3 and R4 are nothing; A is S, S═O or O═S═O; R1 and R2 are independently hydrogen, lower alkyl, halogen, hydroxy or lower alkoxy, (un)substituted aryl, (un)substituted arylalkyl, (un)substituted heteroaryl or(un)substituted heteroarylakyl; R3 and R4 independently represent hydrogen, lower alkyl, cycloalkyl, aminoalkyl, mono- or dialkylaminoalkyl, (un)substituted aryl or (un)substituted heteroaryl; R5 represents a (un)substituted carbocyclic group containing from 3-7 members, up to two of which members are optionally hetero atoms; or R5 is (CR6R7)—(CH2)n—XR8R9; X is S or N; R6, R7, R8, R9, and n are as defined in the specification. The compounds are useful in the treatment and prevention of the AIDS virus. Intermediates useful in the preparation of the final products, pharmaceutical compositions containing the final products are also taught.