“…The 1,3,5-triazinyl l-amino acid derivatives 1a-g, 2a,b,d,e,g and 3a,b,d,e,g were prepared previously in our laboratory. [38] Unless otherwise stated, normal workup from organic solvents involved drying over Na 2 SO 4 and rotary evaporation. TLC was performed General procedure for the synthesis of N-(4,6-dipiperidino-1,3, 5-triazin-2-yl) dipeptide ethyl esters (5 a,b,d,e,g):H ATU( 0.19 g, 0.5 mmol) was added to an ice-cold solution of the N a -(4,6-dipiperidino-1,3,5-triazin-2-yl)amino acid (0.5 mmol) and DIEA (0.17 mL, 1mmol) in DMF (2 mL) with stirring.…”