3'-aminocarbonyloxy paclitaxels

A compound of formula I, or a pharmaceutically acceptable salt thereof ##STR59## wherein R.sup.1 is hydroxy, --OC(O)R.sup.x or --OC(O)OR.sup.x ;

• R.sup.2 is hydrogen, hydroxy, methoxy, --OC(O)R.sup.x or --OC(O)OR.sup.x ;
• R.sup.2' is hydrogen, hydroxy or fluoro;
• R.sup.6' is hydrogen or hydroxy;
• R.sup.6 is hydrogen, or R.sup.2 and R.sup.6 together can form oxirane ring or a bond;
• R.sup.3 is hydrogen, hydroxy, C.sub.1-6 alkyloxy, --OCONR.sup.14 R.sup.15, --OC(O)R.sup.x or --OC(O)OR.sup.x ;
• R.sup.8 is methyl or hydroxymethyl, or R.sup.8 and R.sup.2 together form cyclopropane ring;
• R.sup.9 is hydroxy or --OC(O)R.sup.x ;
• with the proviso that when R.sup.8 and R.sup.2 form cyclopropane ring, R.sup.2' is hydrogen;
• when R.sup.2 and R.sup.6 form oxirane ring or double bond, R.sup.2' and R.sup.6' are hydrogen;
• when R.sup.2 is hydroxy, methoxy, --OC(O)R.sup.x or --OC(O)OR.sup.x, R.sup.2' is hydrogen;
• when R.sup.2' is fluoro, R.sup.2 is hydrogen;
• one of R.sup.7 or R.sup.7' is hydrogen and the other is hydroxy, --OC(O)R.sup.x or --OC(O)OR.sup.x, or R.sup.7 and R.sup.7' together form an oxo group;
• R.sup.14 and R.sup.15 are independently C.sub.1-6 alkyl, hydrogen, aryl or substituted aryl;
• R.sup.4 and R.sup.5 are independently C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, or --Z--R.sup.10 ;
• Z is a direct bond, C.sub.1-6 alkyl or C.sub.2-6 alkenyl;
• R.sup.10 is aryl, substituted aryl, C.sub.3-6 cycloalkyl or heteroaryl;
• R.sup.11 is --OC(O)R.sup.y or --OC(O)OR.sup.y ;
• R.sup.12 is hydrogen or hydroxy;
• R.sup.y is C.sub.3-6 cycloalkyl or C.sub.1-6 alkyl;
• R.sup.x is C.sub.3-6 cycloalkyl, C.sub.2-6 alkenyl or C.sub.1-6 alkyl, all are optionally substituted with one to six same or different halogen atoms;
• or R.sup.x is a radical of the formula ##STR60## wherein D is a bond or C.sub.1-6 alkyl;
• and R.sup.a, R.sup.b and R.sup.c are independently hydrogen, nitro, cyano, azido, amino, C.sub.1-6 alkylamino, di-C.sub.1-6 alkylamino, halogen, C.sub.1-6 alkyl, hydroxy or C.sub.1-6 alkoxy.