Process for making HIV protease inhibitors

A compound of formula IV ##STR42## wherein:

• stereocenter a is in either the R configuration, the S configuration or is racemic;
• r is an integer from zero through and including 5;
• R.sup.3 is selected from the group consisting of:
• 1) hydrogen,
• 2) --C.sub.1-4 alkyl
• 3) C.sub.5 -C.sub.10 cycloalkyl, optionally substituted with hydroxy,
• 4) C.sub.6 -C.sub.10 aryl, unsubstituted or substituted with one or more of:
• a) halo,
• b) hydroxy,
• c) --NO.sub.2 or --N(R).sub.2,
• d) C.sub.1-4 alkyl,
• e) C.sub.1-3 alkoxy, unsubstituted or substituted with one or more of --OH or C.sub.1-3 alkoxy,
• f) --COOR,
• g) --CON(R).sub.2,
• h) --CH.sub.2 N(R).sub.2,
• i) --CH.sub.2 NHCOR,
• j) --CN,
• k) --CF.sub.3,
• l) --NHCOR,
• m) aryl C.sub.1-3 alkoxy,
• n) aryl,
• o) --NRSO.sub.2 R,
• p) --OP(O)(OR.sub.x).sub.2, or
• q) --R.sup.5, as defined below, or
• 5) monocyclic or bicyclic heterocycle containing from 1 to 3 heteroatoms chosen from the group consisting of N, O, and S, and which is unsubstituted or substituted with R.sup.5 and optionally with one or more of
• a) halo,
• b) C.sub.1-4 alkyl, or
• c) C.sub.1-3 alkoxy;
• R is hydrogen or C.sub.1-4 alkyl;
• R.sub.x is H or aryl;
• and
• R.sup.5 is
• 1) --W--(CH.sub.2).sub.m --NR.sup.6 R.sup.7 wherein W is --O-- or --S--, m is 2, 3, 4 or 5, and R.sup.6 and R.sup.7 are independently selected at each occurrence from:
• a) hydrogen,
• b) C.sub.1-6 alkyl, unsubstituted or substituted with one or more of
• i) C.sub.1-3 alkoxy,
• ii) --OH, or
• iii) --N(R).sub.2,
• c) aromatic heterocycle unsubstituted or substituted with one or more of
• i) C.sub.1-4 alkyl, or
• ii) --N(R).sub.2,
• d) or R.sup.6 and R.sup.7 are joined together with the nitrogen to which they are attached to form a 5-7 member heterocycle containing up to two additional heteroatoms selected from --N(R), --O--, --S--, --S(O)-- or --S(0).sub.2 --, the heterocycle optionally substituted with C.sub.1-4 alkyl,
• 2) --(CH.sub.2).sub.q --NR.sup.6 R.sup.7 wherein q is an integer from 1-5, and R.sup.6 and R.sup.7 are defined above, except that R.sup.6 or R.sup.7 are not H or unsubstituted C.sub.1-6 alkyl, or
• 3) benzofuryl, indolyl, azacycloalkyl, azabicyclo C.sub.7-11 cycloalkyl, or benzopiperidinyl, unsubstituted or substituted with C.sub.1-4 alkyl.