Premium
New synthetic approaches to 3‐carhoxamides of 4‐hydroxy‐2 H ‐1,2‐benzothiazine 1,1‐dioxide
Author(s) -
Lombardino Joseph G.,
Watson Harry A.
Publication year - 1976
Publication title -
journal of heterocyclic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.321
H-Index - 59
eISSN - 1943-5193
pISSN - 0022-152X
DOI - 10.1002/jhet.5570130226
Subject(s) - benzothiazine , chemistry , ether , yield (engineering) , carboxamide , stereochemistry , bond cleavage , medicinal chemistry , organic chemistry , catalysis , materials science , metallurgy
Two new synthetic approaches to the title compounds are reported. In the first of these, starting with N ‐carbobenzyloxysarcosine, four synthetic steps are employed to finally assemble the C 3 C 4 bond of the 1,2‐benzothiazine ring. In the second approach, an enol ether is employed as a protecting group to allow formation of the 3‐carboxamide function, which is followed by cleavage of the ether function to yield the desired 4‐hydroxy‐1,2‐benzothiazine‐3‐carboxamide 1,1‐dioxide.