Patent ID: 8093231

Claim:
A compound of formula: where: R 1 is alkyl, optionally substituted with one to three groups selected from —OH, —C(O)OH, —SO 2 OH, each R is independently hydrogen, optionally R′-substituted alkyl, optionally R′-substituted heteroalkyl, optionally R′-substituted aryl, optionally R′-substituted heteroaryl, optionally R′-substituted aralkyl, optionally R′-substituted heteroaralkyl, or two R groups form a 4- or 5-member optionally R′-substituted alkanediyl or optionally R′-substituted heteroalkanediyl; each R′ is, independently, 1 to 3 substituents selected from halo, —SH, —NH 2 , or —C(O)Oalkyl; and X is a halogen; or its pharmaceutically acceptable salt.