Retroviral protease inhibitors sulfonilalcano-ylamino hydroxyethylamino sulfonamide.

Compound represented by the formula * ** or a pharmaceutically acceptable salt, prodrug or ester thereof, wherein t represents 0, 1 or 2; R1 represents hydrogen, alkyl having 1 to 5 carbon atoms, alkenyl having 2 to 5 carbon atoms, alkynyl with 2 to 5 carbon atoms, I hydroxyalkyl having 1 to 3 carbon atoms, alkoxyalkyl having 1 to 3 carbon atoms alkyl and 1 to 3 carbon atoms alkoxy, cyanoalkyl with 1 to 3 alkyl carbon atoms, -CH2CONH2, -CH2CH2CONH2, -CH2S (O) 2NH2, -CH2SCH3, -CH2S (O) CH3 or -CH2S (O) 2CH3; R2 represents alkyl having 1 to 5 carbon atoms, aralkyl having 1 to 3 carbon atoms, alkylthioalkyl with 1 to 3 carbon atoms alkyl, arylthioalkyl with 1 to 3 carbon atoms alkyl or cycloalkylalkyl having 1 to 3 alkyl carbon atoms and 3-6 carbon atoms ring members; R3 represents radicals such as an alkyl radical having 1 to 5 carbon atoms, cycloalkyl of 5 to 8 ring members or cycloalkylmethyl radical of 3-6 ring members; R4 represents radicals 5- to 6-membered ring of the radicals benzo condensed or 5- to 6-membered ring of the fused benzo, wherein the sulfonamide sulfur atom is bound to a carbon atom of the benzo ring.