As shown in SCHEME IV, a compound of formula (r) may be obtained by reactions among a carbonyl compound of formula (I) wherein R1, R2 and R3 are as defined in formula (I) and X is an appropriate leaving group such as Cl, Br, OH, OR, SR, NR2, N(OR1)R or the like and organometallic reagent obtained by first base treatment such as NaH on compound (q) wherein R13 is as defined above followed by subseq