CN
- Synthesis and tautomerization of hydroxylated isoflavones bearing heterocyclic hemi-aminals.
Synthesis and tautomerization of hydroxylated isoflavones bearing heterocyclic hemi-aminals.
Organic & biomolecular chemistry (2014-11-22)
Mykhaylo S Frasinyuk, Svitlana P Bondarenko, Volodymyr P Khilya, Chunming Liu, David S Watt, Vitaliy M Sviripa
PMID25412895
ABSTRACT
The aminomethylation of hydroxylated isoflavones with 2-aminoethanol, 3-amino-1-propanol, 4-amino-1-butanol, and 5-amino-1-pentanol in the presence of excess formaldehyde led principally to 9-(2-hydroalkyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]-oxazin-4-ones 4 and/or the tautomeric 7-hydroxy-8-(1,3-oxazepan-3-ylmethyl)-4H-chromen-4-ones 5. The ratio of these tautomers was dependent on solvent polarity, electronic effects of aryl substituents in the isoflavone and the structure of the amino alcohol. NMR studies confirmed the interconversion of tautomeric forms.
MATERIALS
Product Number
Brand
Product Description
Sigma-Aldrich
Chloroform-d, ≥99.8 atom % D, contains 0.5 wt. % silver foil as stabilizer, 0.03 % (v/v) TMS
Sigma-Aldrich
Chloroform-d, "100%", 99.96 atom % D, contains 0.5 wt. % silver wire as stabilizer
Sigma-Aldrich
Deuterium oxide, 99.9 atom % D, contains 0.05 wt. % 3-(trimethylsilyl)propionic-2,2,3,3-d4 acid, sodium salt
Sigma-Aldrich
Deuterium oxide, 99.9 atom % D, contains 0.75 wt. % 3-(trimethylsilyl)propionic-2,2,3,3-d4 acid, sodium salt
Sigma-Aldrich
Deuterium oxide, 99.9 atom % D, contains 1 % (w/w) 3-(trimethylsilyl)-1-propanesulfonic acid, sodium salt (DSS)