Patent ID: 8569275

Claim:
A compound having the structure or a salt thereof, wherein the dotted line is an optional double bond; R 1 is —OH, ═O, —SH, amide, ester or ether; R 2 is —OH, ═O, halogen, alkyl, ester or ether; R 3 is —H, —OH, halogen, alkyl, ester or ether; R 4 is a heterocycle; R 5 and R 6 independently are —H, —CH 3 , —C 2 H 5 , —C 3 H 7 , alkyl, —OH, —F, —Cl, —Br or —I; R 7 is —CH 2 —, —C(halogen) 2 —, CH(α-alkyl), —CH(β-alkyl), —CH(α-OH), —CH(β-OH) or —C(alkyl) 2 ; R 9 is —CH 2 —, —CH(α-OH), —CH(β-OH) or —C(alkyl) 2 — or R 9 is ═CH— when the optional double bond is present, R 10A , R 10B , R 10C and R 10D independently are —H, alkyl, —CH 3 , halogen, —SR PR or —OR PR and each R 10A , R 10B , R 10C and R 10D is independently in the α-configuration or the β-configuration; and R PR independently are —H or a protecting group.