Patent ID: 8455665

Claim:
A method of preparing a compound of formula I: where R 1 is selected from —CH 2 OH, —C 1-2 alkylene-O—C 1-6 alkyl, —C 1-2 alkylene-S—C 1-6 alkyl, —C 1-2 alkylene-O-phenyl, —C 1-2 alkylene-S-phenyl, —C 1-2 alkylene-O-benzyl, —C 1-2 alkylene-S-benzyl, tetrahydropyranyl, and tetrahydrofuranyl; and R 2 through R 6 are independently selected from hydrogen, halo, —C 1-6 alkyl, —CF 3 , —O—C 1-6 alkyl, —CN, —C(O)—C 1-6 alkyl, —S—C 1-6 alkyl, —C 3-8 cycloalkyl, and —NO 2 ; or R 4 and R 5 are taken together to form —CH═CH—CH═CH—; or R 5 and R 6 are taken together to form —CH—CH═CH—CH—, the process comprising deprotecting a compound of the formula: where P represents an amino-protecting group, to provide a compound of formula I, or a salt thereof.