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Updated: Jan 19, 2026
Sedatives and Hypnotics Drugs: Barbiturates
Synthesis and structure of push-pull merocyanines based on barbituric and thio-barbituric acid
Georgii Bogdanov1, John P Tillotson2, Jenna Bustos1
1Department of Chemistry, New Mexico Highlands University, Las Vegas, New Mexico, 87701, USA.
Abstract:
Two compounds, 1,3-diethyl-5-{(2E,4E)-6-[(E)-1,3,3-tri-methyl-indolin-2-yl-idene]hexa-2,4-dien-1-yl-idene}pyrimidine-2,4,6(1H,3H,5H)-trione or TMI, C25H29N3O3, and 1,3-diethyl-2-sulfanyl-idene-5-[2-(1,3,3-tri-methyl-indolin-2-yl-idene)ethyl-idene]di-hydro-pyrimidine-4,6(1H,5H)-dione or DTB, C21H25N3O2S, have been crystallized and studied. These compounds contain the same indole derivative donor group and differ in their acceptor groups (in TMI it contains oxygen in the para position, and in DTB sulfur) and the length of the π-bridge. In both materials, mol-ecules are packed in a herringbone manner with differences in the twist and fold angles. In both structures, the mol-ecules are connected by weak C-H⋯O and/or C-H⋯S bonds.
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