Patent ID: 7396930

Claim:
A process for producing a compound having the following formula (6): wherein R 2 represents a hydrogen atom or an amino protecting group, G 1 represents a C 1 -C 6 alkylene group and Ar represents an unsubstituted phenyl group or a phenyl group substituted with at least one group from Substituent group α; Substituent group α is selected from the group consisting of a C 1 -C 6 alkyl group, a C 1 -C 6 alkoxy group and a C 1 -C 6 alkylthio group, comprising reacting a compound having the formula (1): wherein X 1 and X 2 are the same or different and each represents a halogen atom, and G 1 and Ar have the same meanings as defined above, with a compound having the formula (2): wherein R 1 represents a thiol protecting group, to produce a compound represented by the formula (3): wherein R 1 , G 1 , X 2 and Ar have the same meanings as defined above, and after reacting the compound of formula (3) with a metal or organometallic reagent that forms a carbanion of the compound of formula (3), reacting a compound having the formula (4): wherein R 2 has the same meaning as defined above, with the resulting reaction mixture to produce a compound having the formula (5): wherein R 1 , R 2 , G 1 and Ar have the same meanings as defined above, carrying out a dehydration reaction after removal of the group R 1 of the compound having the formula (5), and optionally protecting the nitrogen atom with an amino protecting group.