75218-47-2

Upstream product

• 59311-67-0 2-(3-thienyl)ethylamine 
• 29973-91-9 4-benzyloxy-3-methoxyphenylacetic acid 
• 75218-45-0 N-(3-thienyl-β-ethyl)-4-benzyloxy-3-methoxyphenylacetamide 

Downstream Products

• 75218-49-4 7-(4-Benzyloxy-3-methoxy-benzyl)-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine; hydrochloride 
• 75218-51-8 8-Benzyloxy-9-methoxy-4,6,11,11a-tetrahydro-5H-1-thia-5a-aza-cyclopenta[a]anthracene; hydrochloride 
• 688301-90-8 9-benzyloxy-10-methoxy-7H-4,5,12,12a-tetahydrobenzothieno<2,3-a>quinolizine 
• 781565-01-3 7-(4'-benzyloxy-3'-methoxybenzyl)-4,5,6,7-tetrathieno<2,3-c>pyridine 

Relevant academic research and scientific papers

STUDIES ON HETEROCYCLIC COMPOUNDS VI. Synthesis of Thiophene Isoesters of Protoberberine Alkaloids

Synthesis of thiophene isosters of protoberberine alkaloids (6, 12, 19) is described.The Mannich type reaction of the tetrahydroisoquinolines (5, 11) and the thienopyridine (18) with formaldehyde in glacial acetic acid afforded the title compounds.Cyclization of the tetrahydroisoquinoline derivative (23) failed to furnish the D-ring protoberberine isoster (25), but gave an unexpected product, the oxazepinoisoquinoline derivative (24).The conversion of the compound (24) to the 2-substituted isoquinoline (27) is also described.