212568-81-5

Upstream product

• 3081-24-1 H-Phe-OEt 
• 212568-76-8 5-Chloro-N²,N²,N⁷,N⁷-tetramethyl-pyrimido[4,5-d]pyrimidine-2,4,7-triamine 

Relevant academic research and scientific papers

A novel fused heterocyclic system - Synthesis of substituted 9,10- dihydro- 1,3,4,6,7,10-hexaazacyclohepta[de]naphthalen-8(7H)-ones

4-Amino-5-chloro-2,7-bis(dimethylamino)pyrimido[4,5-d]pyrimidine (5) was prepared starting from 1,1-diamino-2,2-dicyanoethylene (1) and dichloromethylenedimethylimmonium chloride (2). After reacting with α- aminoacidic esters, 5 was converted into a series of new pyrimido[4,5- d]pyrimidines (7), which underwent cyclization to yield substituted 9,10- dihydro-1,3,4,6,7,10-hexaazacyclohepta[de]naphthalen-8(7H)-ones (8).