Topic
Benzopyran
About: Benzopyran is a research topic. Over the lifetime, 1889 publications have been published within this topic receiving 15235 citations.
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TL;DR: In this article, a mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans was proposed.
Abstract: Intramolecular substitutions leading to cyclizations with the ejection of chlorine have been noticed during mass spectral fragmentation of 4-chloro-3-(N-aryliminomethyl) (2H) benzopyrans and benzothiopyrans. Very interesting ortho effects involving intramolecular substitutions have also been observed in 6-methyl-4-diloro-3-[N-(2-methoxyphenyliminomethyl)] (2H) benzopyran and 6-methyl-4-chloro-3-[N-(2-chlorophenyliminomethyl)]-(2H) benzopyran. The proposed fragmentation mechanisms have been supported by the accurate mass measurements and linked scan studies.
4 citations
4 citations
Patent•
13 Oct 1977
TL;DR: In this paper, a list of non-toxic, pharmaceutically acceptable compounds for the prevention of allergic and asthmatic reactions is presented, including carboxy, alkoxy carbonyl, carboxamide, cyano or tetrazolo.
Abstract: Compounds of formula I: ##STR1## wherein Y is hydrogen, lower alkyl, halogen or lower alkoxy; X is carboxy, alkoxycarbonyl, carboxamide, cyano or tetrazolo, and their non-toxic, pharmaceutically acceptable salts are disclosed. These compounds are useful in the prevention of allergic and asthmatic reactions.
4 citations
TL;DR: In this article, the 1H and 13C NMR spectra of the labeled hemiacetal [3a,8a-13C2]1 showed that this compound exists in solution in equilibrium with the benzopyran derivative 2.
4 citations
4 citations