77117-12-5Relevant academic research and scientific papers
A Novel Pentacyclic Pyridine Dilactone. 7-Methylbenzopyranobenzoxacinopyridine-6,16-dione
Rajyalakshmi, K.,Srinivasan, V. R.
, p. 1737 - 1739 (2007/10/02)
When equimolar quantities of salicylaldehyde 2 and ethyl 3-amino-2-butenoate 3 or its constituents (ethyl 3-oxobutanoate and ammonia) were refluxed on a steam-bath for 6 hours with a trace of acetic acid, two products, a pentacyclic pyridine dilactone 4 and 3-acetyl coumarin 5, resulted in 15percent and 45percent yields, respectively.The structure of 4 was elucidated as 7-methylbenzopyranobenzoxacinopyridine-6,16-dione on the basis of its spectral data.The mechanism of its formation has been discussed.The reaction has been extended to three more substituted salicylaldehydes.
