1,8-Diazabicyclo(5.4.0)undec-7-ene → methyl (E)-3-(8-({[4-(tert-butyl)-1,3-thiazol-2-yl]amino}carbonyl)-2-{3-[(dimethylamino)carbonyl]piperidino}-4-oxo-4H-pyrido[1,2-a]pyrimidin-3-yl)-2-propenoate

Participants

Reaction Steps

The N8-[4-(tert-butyl)-1,3-thiazol-2-yl]-2-{3-[(dimethylamino)carbonyl]-piperidino}-3-formyl-4-oxo-4 H-pyrido[1,2-a]pyrimidine-8-carboxamide (84.2 mg, 0.18 mmol) obtained in (B) was dissolved in tetrahydrofuran (10 ml), added with lithium chloride (45.3 mg, 1.07 mmol), and added dropwise with bis(2,2,2-trifluoroethyl)-(methoxycarbonylmethyl)phosphonate (112.9 μl, 0.53 mmol) and 1,8-diazabicyclo-[5,4,0]undec-7-ene (73.4 μl, 0.53 mmol). After the reaction solution was stirred at room temperature for 2 hours, the solvent was evaporated, and the residue was purified by preparative TLC (chloroform:methanol=20:1, v/v) to obtain the title compound (63.7 mg, 68.2%) as a mixture of orange oil and solid.

Provenance & Evidence