320338-51-0

Upstream product

• 53074-16-1 5,6-dimethyl-2-methylthio-3,4-dihydrothieno[2,3-d]pyrimidin-4-one 
• 100-52-7 benzaldehyde 
• 53074-14-9 2-hydrazino-5,6-dimethylthieno<2,3-d>pyrimidin-4(3H)-one 

Relevant academic research and scientific papers

4′,x-Seco and 4′,x-4′,5′-Diseco C-Nucleosides from 2-Hydrazino-(3H)-thieno[2,3-d]pyrimidin-4-ones

Cyclization of 2-hydrazino-5,6-dimethyl-3H-thieno[2,3-d]pyrimidin-4-one (1) with acetic acid gave 3,6,7-trimethyl-1,2,4-triazolo[3,4-a]thieno[2,3-d] pyrimidin-5-one (5) whose Dimroth rearrangement gave 2,6,7-trimethyl-1,2,4-triazolo[3,4-a]thieno[2,3-d]pyrimidin-5-one (11). Alternatively, 5 was obtained from the dehydrogenative cyclization of acetaldehyde 5,6-dimethyl-4-3H-oxo-thieno[2,3-d]pyrimidin-2-yl hydrazone (7). Reaction of 1 and 2 with a number of sugars gave the respective hydrazones 19 and 20. Those of the D-glucose exist in the cyclic pyranosyl structure in addition to minor amounts of the acyclic structure. Dehydrogenative cyclization of the sugar hydrazones gave the respective fused tricyclic compounds 25 and 26.

Synthesis and reactions of polynuclear heterocycles with new ring systems

Condensation of 5,6-dimethyl-2-hydrazino-3,4-dihydrothieno[2,3-d]pyrimidin-4-one (2) with aromatic aldehydes gave the arylhydrazones 3a-c which cyclized into thienotriazolopyrimidin-5- one 4a-c. Reactions of 2 with aliphatic acids afforded the thienotriazolopyrimidin-5-one a,b. Also, reaction of 2 with each of carbon disulfide and nitrous acid afforded 3-mercaptothienotriazolopyrimidin-5-one 7, and tetrazolothienopyrimidin-5-one 8, respectively, the latter compound 8could be reduced to 2-aminothienopyrimidin-4-one 9. On the other hand, 2-hydrazino derivative 2 condensed with α-haloketones yielded 3-substituted-thienopyrimidotriazin-6-one 10a,b with new ring system, and with β-diketones, β-ketoesters to form 2- (1-pyrazolyl) derivatives 13a-c, 14. The 2-pyrazolinone derivative 15 condensed with aromatic aldehydes to afford arylidene derivatives 16a-c. Also, reaction of 2 with ethyl cyanoacetate yielded 2-(pyrazolyl) derivatives 17.