Cyclic sulfone containing retroviral protease inhibitors

Compound of formula A:

• ##STR71## or a pharmaceutically acceptable salt, prodrug or ester thereof, wherein Y' and Y independently represent O or S;
• t represents 0 or 1;
• t' represents 1 or 2;
• u represents 0, 1, or 2;
• R.sup.40, R.sup.41, R.sup.42, R.sup.43, and R.sup.48 independently represent hydrogen or alkyl;
• R.sup.44, R.sup.45, R.sup.46 and R.sup.47 independently represent hydrogen, alkyl or hydroxy;
• or one of (a) R.sup.40 together with R.sup.48, (b) R.sup.43 together with R.sup.45, (c) R.sup.45 together with R.sup.47 or (d) R.sup.47 together with R.sup.48 represent a bond, or;
• one of (a) R.sup.44 together with R.sup.45 and the carbon atom to which they are attached, or (b) R.sup.46 together with R.sup.47 and the carbon atom to which they are attached represent a carbonyl;
• R.sup.6 represents hydrogen or alkyl radicals;
• R.sup.2 represents alkyl, aryl, cycloalkyl, cycloalkylalkyl, or aralkyl radicals, which radicals are optionally substituted with a substituent selected from the group consisting of alkyl radicals, --NO.sub.2, CN, CF.sub.3, --OR.sup.9, --SR.sup.9, and halogen radicals, wherein R.sup.9 represents hydrogen or alkyl radicals;
• and Q represents a radical of formula (B1), (B2) (B3), (B4) or (B5):
• ##STR72## wherein R.sup.3 represents hydrogen, alkyl, haloalkyl, alkenyl, alkynyl, hydroxyalkyl, alkoxyalkyl, cycloalkyl, cycloalkylalkyl, aryl, aralkyl, aminoalkyl, mono- and disubstituted aminoalkyl radicals wherein said substituents are selected from alkyl, aryl, aralkyl, cycloalkyl, and cycloalkylalkyl, or in the case of a disubstituted amino alkyl radical, said substituents along with the nitrogen atom to which they are attached, form a thioalkyl, a alkylthioalkyl, a arylthioalkyl radical or the sulfone or sulfoxide derivatives thereof;
• R.sup.4 and R.sup.5 independently represent radicals as defined for R.sup.3 ;
• q represents 1 or 2;
• n represents an integer from 0 to 6;
• R.sup.7 and R.sup.7" each independently represent radicals as defined for R.sup.3 ;
• or
• R.sup.7 and R.sup.7" each represent an amino acid side chain selected from the group consisting of valine, isoleucine, alanine, alloisoleucine, asparagine, leucine, glutamine or t-butylglycine;
• or
• R.sup.7 and R.sup.7" together with the carbon atom to which they are attached form a cycloalkyl radical;
• and
• R.sup.8 represents cyano, hydroxyl, alkyl, alkoxy, cycloalkyl, aryl, aralkyl, or radicals represented by the formulae C(O)R.sup.10, CO.sub.2 R.sup.10, SO.sub.2 R.sup.10, SR.sup.10, CF.sub.3, NR.sup.10 R.sup.11 or CONR.sup.10 R.sup.11, where R.sup.10 and R.sup.11, independently represent the radicals for R.sup.3.