52881-33-1

Upstream product

• 51808-84-5 2-(bromomethyl)-5-oxo-2,3,4,5,6,7,8,9-octahydrobenzothieno<3,2-e>thiazolo<2,3-b>pyrimidine 
• 42062-91-9 3-allyl-2-mercapto-5,6,7,8-tetrahydrobenzo[4,5]thieno[2,3-d]pyrimidin-4(3H)-one 
• 42062-89-5 2-(3-allyl-thioureido)-4,5,6,7-tetrahydro-benzo[b]thiophene-3-carboxylic acid ethyl ester 

Relevant academic research and scientific papers

Synthesis of 2-methylene-2,3-dihydro-and 2-methyl-5H-thiazolo[3.2-a]thieno[2.3-d]pyrimidines

The title substances and their [1]benzothieno analogues were synthesized by reaction of 3-allyl-2-mercapto-([1]benzo)thieno-[2.3-d]pyrimidine-4(3 H)-ones with Br2 to 2-bromomethyl-2.3-dihydro-thiazolo[3.2-a]([1]benzo-)thieno[2.3-d]pyrimidine-5-ones, which on treatment with morpholine did not give the corresponding morpholine derivatives but elimination to the exocyclic double bond. These 2-methylene-2.3-dihydro-products were isomerized by H2SO4 to the corresponding 2-methyl compounds.