Patent ID: 7291728

Claim:
A compound of formula I: wherein R 1 and R 2 are independently H, halogen, protected or unprotected hydroxy, trialkylsilyloxy, substituted or unsubstituted alkyl or cycloalkyl, substituted or unsubstituted alkoxy or aryloxy, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl, nitro, amino, mercapto or alkylthio; R 3 and R 4 are independently H, substituted alkyl, substituted or unsubstituted alkoxy or aryloxy, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl; Z is —(CRaRb) n — wherein n is 1, and Ra and Rb are each independently hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryloxy, substituted or unsubstituted amino or halogen; Y is —O—, —S—, or —C(O); W is —CRaRb-Q, wherein Ra and Rb are as previously defined and Q is substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl, substituted or unsubstituted alkenyl; or a salt thereof.