Process for preparing a compound having inhibitory activity of HIV integrase

A method of producing a compound shown by formula (Y1) or the formula (Y2) or a salt thereof: ** Formula ** (in which Rx is carbocyclyl optionally substituted with substituent E, heterocyclyl optionally substituted with substituent E , carbocyclyl lower optionally substituted alkyl substituent E or heterocyclyl optionally substituted with substituent E and the substituent E is as lower alkyl defined below) comprising the steps of: (Step C) reacting a compound shown by formula (X3) or a salt thereof: ** ** Formula (wherein R1d is hydrogen, halogen, lower alkyloxy optionally substituted with substituent E, carbocyclyl optionally substituted with lower alkyloxy substituent E, heterocyclyl lower alkyloxy optionally substituted with substituent E or OSi ( 1e) 3, the R1e are each independently optionally substituted with lower alkyl substituent E, carbocyclyl optionally substituted with substituent E, heterocyclyl optionally substituted with substituent E, carbocyclyl lower alkyl optionally substituted with substituent E or heterocyclyl optionally substituted with substituent E, R2d is hydrogen lower alkyl optionally substituted with substituent E lower alkyl, carbocyclyl optionally substituted with lower alkyl substituent E or heterocyclyl lower alkyl optionally substituted with substituent E, R4d is optionally substituted with lower alkyl substituent E, carbocyclyl lower optionally substituted with substituent E or heterocyclyl optionally substituted with lower alkyl substituent alkyl E, and substituent E: halogen, cyano, hydroxy, carboxy, formyl, amino, oxo, nitro, lower alkyl, halogen lower alkyl, lower alkyloxy, carbocyclyl optionally substituted with substituent F, heterocyclyl optionally substituted with substituent F, carbocyclyl lower alkyloxy optionally substituted with substituent F, heterocyclyl lower alkyloxy optionally substituted with substituent F, carbocyclyl lower alkylthio optionally substituted with substituent F, heterocyclyl lower alkylthio optionally substituted with substituent F, carbocyclyl lower alkylamino optionally substituted with substituent F, heterocyclyl lower alkylamino optionally substituted with substituent F, carbocyclyloxy optionally substituted with substituent F, heterocyclyloxy optionally substituted with substituent F, carbociclilcarbonilo optionally substituted with substituent F, heterocyclylcarbonyl optionally substituted with substituent F, carbociclilaminocarbonilo optionally substituted with substituent F, heterocyclylaminocarbonyl optionally substituted with substituent F, lower alkyloxy, halogen, lower alkyloxy lower alkyl , lower alkyloxy lower alkyloxy, lower alkylcarbonyl, lower alkyloxycarbonyl, alkyloxy carbonylamino lower, lower alkylamino, lower alkylcarbonylamino, lower alkylaminocarbonyl, lower alkylsulfonyl and lower alkylsulfonylamino; F substituent: halogen, hydroxy, carboxy, amino, oxo, nitro, lower alkyl, halogen lower alkyl, lower alkyloxy and amino protecting group). with a compound shown by the formula (V3), or a salt thereof: H2N-6d (V3) (wherein R6d is optionally substituted with substituent E or lower alkenyl optionally substituted with substituent E lower alkyl and the substituent E is as is defined above), to obtain a compound shown by the formula (X4) or a salt thereof: ** ** formula (wherein each symbol is as defined above); (Step D) reacting a compound shown by formula (X4) or a salt thereof with (R) -3-amino-butan-1-ol or (S) -2-amino-propan-1-ol to obtain a compound shown by the formula (X5) or formula (X5 '): ** ** formula (wherein each symbol is as defined above).