4-Aryl-2,3-dihydro-177-pyrido pyrimidine-1,3-diones

Characteristic H NMR data of (4a/ ,55)- and (4n5,5R)-2-substituted 5- [A-(/e/ /-butoxycarbonyl)-L-tryptophyl]amino perhydropyrido[l,2-c]pyri-midine-l,3-diones were tabulated (01JMC2219). C CPMASS NMR data of 4-(4-methoxyphenyl)perhydropyrido[l,2-c]pyrimidine were reported (00JST73). C NMR data were reported for eight 4-aryl-2,3,5,6,7,8-hexahydro-l//-pyrido[l,2-c]pyrimidin-l,3-diones in the solid state and in CDCI3 solution (00JPO213). The structure of 4-aryl-3,4-dihydro-2//-pyrido [l,2-c]pyrimidine-l,3-diones and their 2,3,5,6,7,8-hexahydro derivatives were characterized by H and C NMR data (99JHC389). Conformational analysis of 6-methyl-2,3,4,6,7,ll/)-hexahydro-l//-pyrimido[6,l-n]isoquino-lin-2-ones 138 and 139 were carried out by H and C NMR studies (97LA1165). 

Cyclocondensation of a-aryl-2-pyridylacetamides and 2-(3,4-dihydroiso-quinolin-l-yl)acetamide with Et2C03 in the presence of NaOEt in boiling EtOH afforded 4-aryl-2,3-dihydro-l//-pyrido[l,2-c]pyrimidine-l,3-diones (99JHC389) and 6,7-dihydro-4//-pyrimido[6,1 -a]isoquinoline-2,4-dione (98MIP15), respectively. 

The structures of 4-aryl-2,3-dihydro-lH-pyrido[l,2-c]pyrimidine-l,3-diones hydrochlorides 50 were characterized by solid-state 13C CPMAS NMR spectroscopy (08JST325). 

Cyano-2,3-dihydro-lH-pyrido[l,2-c]pyrimidin-l- and -3-ones were N-alkylated with Mel in the presence of K2CC>3 in DMF (05MI1). 4-Aryl-2,3-dihydro-lH-pyrido[l,2-c]pyrimidine-l, 3-diones were N(2)-alkylated with 1,4-dibromobutane in the presence of K2C03 in boiling acetone for 2 h in 57-95% yields (06EJM125). 

Piperidyl)indoles were N-alkylated with 4-aryl-2-(4-bromobutyl)-2,3-dihydro-lH-pyrido[l,2-c]pyrimidinel,3-diones in the presence of K2C03 and a catalytic amount of KI in boiling MeCN for 4-5 h in 50-90% yields (09EJC1710). The bromo atom of 2-(4-bromobutyl)-4-aryl-2,3-dihydro-lH-pyrido[l,2-c]pyrimidine-l,3-diones was replaced by 4-(het)arylpiperazino... 

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