An Efficient Synthesis of Novel Hexahydropyrido[2,3-d]pyrimidine Derivatives from (Arylmethylidene)pyruvic Acids (=(3E)-4-Aryl-2-oxobut-3-enoic Acids) in Aqueous Media

✍ Scribed by Saeed Balalaie; Shahrzad Abdolmohammadi; Bita Soleimanifard

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: German
• Weight: 152 KB
• Volume: 92
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.200800318

✦ Synopsis

Abstract

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A series of new hexahydropyrido[2,3‐d]pyrimidine derivatives 3 were synthesized by the cyclocondensation reaction of (arylmethylidene)pyruvic acids (=(3__E__)‐4‐aryl‐2‐oxobut‐3‐enoic acids) 1 and 6‐aminouracils (=6‐aminopyrimidine‐2,4(1__H__,3__H__)‐diones) 2 in H~2~O under reflux conditions (Scheme 1, Table). This novel protocol has the advantages of facility, of easy workup, of high yields, and of an environmentally benign procedure. The structures of compounds 3a–3f were corroborated spectroscopically (IR, ^1^H‐ and ^13^C‐NMR, and EI‐MS). A plausible mechanism for the reaction is proposed (Scheme 2).