Peptides

A compound of formula I

• wherein
• each R is H, —R5, —OR5, —C(O)R5, —R5C(O)R6, —C(O)OR5, —R5C(O)OR6, —R5OC(O)R6, —R5OC(O)OR6, —R5NR6C(O)R7, —R5C(O)NR6R7, —C(O)NR6R7, —R6OC(O)NR6R7, —R5NR6C(O)NR7R8, —R5NR6C(O)OR7, —R5—O—R6, —R5—NR6R7, —R5—S—R6, —R5—SOm—R6, —R5OR6—O—R7, —R5NR6R7—O—R8, —R5SOmR6—O—R7, —C(O)R5—O—R6, —C(O)OR5—O—R6, —R5C(O)R6—O—R7, —R5C(O)OR6—O—R7, —R5OC(O)R6—O—R7, —R5OC(O)OR6—O—R7, —R5NR6C(O)R7—O—R8, —C(O)NR5R6—O—R7, —R5C(O)NR6R7—O—R8, —R5OC(O)NR6R7—O—R8, —R5NR6C(O)NR7R8—O—R9, —R5NR6C(O)OR7—O—R8, —R5OR6—S—R7, —R5NR6R7—S—R8, —R5SOmR6—S—R7, —C(O)R5—S—R6, —C(O)OR5—S—R6, —R5C(O)R6—S—R7, —R5C(O)OR6—S—R7, —R5OC(O)R6—S—R7, —R5OC(O)OR6—S—R7, —R5NR6C(O)R7—S—R8, —C(O)NR5R6—S—R7, —R5C(O)NR6R7—S—R8, —R5OC(O)NR6R7—S—R8, —R5NR6C(O)NR7R8—S—R9, —R5NR6C(O)OR7—S—R8, —R5OR6—NR7R8, —R5NR6R7—NR8R9, —R5SOmR6—NR7R8, —C(O)R5—NR6R8, —C(O)OR5—NR6R8, —R5C(O)R6—NR7R8, —R5C(O)OR6—NR7R8, —R5OC(O)R6—NR7R8, —R5OC(O)OR6—NR7R8, —R5NR6C(O)R7—NR8R9, —C(O)NR5R6—NR7R8, —R5C(O)NR6R7—NR8R9, —R5OC(O)NR6R7—NR8R9, —R5NR6C(O)NR7R8—NHR9, or —R5NR6C(O)OR7—NR8R9′,
• where R5, R6, R7, R8 and R9 are each independently C1-10alkyl, C1-10alkenyl, C1-10alkynyl, C6-10aryl, C6-14aralkyl, C6-14aralkenyl or C6-14aralkynyl and m is 1,2,3 or 4;
• and where R5, R6, R7, R8 and R9 are each unsubstituted or substituted with up to 6 substituents selected from halo, NO2, —OH, C1-4alkyl, —SH, —SO3, —NH2, C1-4acyl, C1-4acyloxy, C1-4alkylamino, C1-4dialkylamino, trihalomethyl, —CN, C1-4alkylthio, C1-4alkylsulfinyl, or C1-4alkylsulfonyl, provided that all the R substituents are not identical, or R forms a cyclic structure, with itself, with R3 or with the carbonyl group attached to the immediately adjacent nitrogen atom;
• X is hydrogen or an O-protecting group or as defined above for R, with the exception that X is not OR5;
• R1 and R2, which may be the same or different, are H, an N-protecting group or as defined above for R, or R1 and R2 are linked together in a 3 to 7 membered heterocyclic ring structure, or either R1 or R2 together with OX signify an amide bond to form a cyclic structure of formula
• wherein Y is H, an amino protecting group or is as defined above for R, Z is —NH—CH(R)—CH(R3)—CO— and m is 1, 2, 3, 4, 5, 6, 7, 8 or 9;
• each R3, which may be the same or different, is as defined above for R, or R3 forms a cyclic structure with the amino group which is alpha to the carbon bearing R3, provided that R and R3 are not both H;
• and
• n is 3, 4, 5, 6, 7, 8, 9, or 10.