Application of the modified Pictet-Spengler cyclization reaction for the preparation of an imidazopyrazine ring: synthesis of new pyrido- and pyrimido-imidazopyrazines.
An efficient and versatile method for the synthesis of imidazopyrazine ring using the modified Pictet-Spengler strategy has been reported. The two step strategy offers rapid assembly of druglike core templates pyridine or pyrimidine and imidazole into new annulated polycyclic skeletons: pyrido- and pyrimido-imidazopyrazines. The rate of endo cyclization of aryl/heteroaryl-amine substrates has been compared with traditionally used aliphatic amine substrates, and results have been discussed in the light of the pK(a) values of amines present in each substrate.
Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow, India.
Sunil
S
Sharma
Bijoy
B
Kundu
D020650:Combinatorial Chemistry Techniques / Q000191:economics / Q000379:methods*; D007093:Imidazoles / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D011719:Pyrazines / Q000138:chemical synthesis* / Q000737:chemistry
D007093:Imidazoles; D011719:Pyrazines