Preparation of New Nitrogen-Bridged Heterocycles 67. Syntheses of .ALPHA.,.ALPHA.'-Bis[(thieno[3,4-b]indolizin-3-yl)thio]-o-, m-, and p-xylene Derivatives and Their Conformational Structures
salts, formed from the S-alkylations of 3-(1-pyridinio)thiophene-2-thiolates with alpha,alpha-dibromo-o-, m-, or p-xylene, provided the corresponding alpha,alpha'-bis[(thieno[3,4-b]indolizin-3-yl)thio]-o-, m-, and p-xylene derivatives in low to good yields. Both (1)H-NMR and UV-Vis spectra of these products supported distinctly the predominance of the gauche-gauche conformation in relation to the two sulfide
Preparation of New Nitrogen-Bridged Heterocycles. 59. Syntheses and Intramolecular Interactions of 3-(Acylmethylthio)- and 3-[(3-Ethoxycarbonyl-2-propenyl)thio]thieno[3,4-<i>b</i>]indolizine Derivatives
作者:Akikazu Kakehi、Hiroyuki Suga、Hirohide Isogai
DOI:10.1248/cpb.55.95
日期:——
Various thieno[3,4-b]indolizinederivatives having an acylmethylthio or (3-ethoxycarbonyl-2-propenyl)thio group at the 3-position which could not be obtained by a conventional method were prepared by a new procedure using cyanoethyl group as a protecting group and their intramolecular arene-pi interactions were investigated. In the (1)H-NMR spectra of these thieno[3,4-b]indolizines, the low-field shifts
Preparation of New Nitrogen-Bridged Heterocycles. 54. Increased Arene-Arene Interactions of 3-(Bicyclic and Tricyclic Arylmethylthio)thieno [3,4-b] indolizine Derivatives
Some thieno[3,4-b]indolizine derivatives having a 1-naphthylmethylthio, 2-methyl-1-naphthylmethylthio, 2-naphthylmethylthio, or 9-anthrylmethylthio group at the 3-position were prepared and their intramolecular arene-arene interactions were investigated. In comparison with 3-(methylthio)thieno[3,4-b]indolizines which have no such interactions, the (1)H-NMR spectra of title compounds showed large high-field
Preparation of New Nitrogen-Bridged Heterocycles. 58. Syntheses and Intramolecular Arene-.PI. Interactions of 3-(Allylthio)- and 3-(Propargylthio)thieno[3,4-b]indolizine Derivatives
Various thieno indolizinederivatives having an allylthio or propargylthio group at the 3-position were prepared and their intramolecular arene-pi interactions were investigated. Their 1H-NMR spectra showed significant low-field shifts (delta 0.10-0.34 ppm) to the 5-proton on the thieno indolizine ring, and this effect was the reverse to that observed in 3-(arylmethylthio)thieno indolizines. However, their
Preparation of New Nitrogen-Bridged Heterocycles. 53. Syntheses of 3-(Benzylthio)thieno[3,4-b]indolizine Derivatives and Their Intramolecular Arene-Arene Interactions.
3-(benzylthio)thieno[3,4-b]indolizinederivatives showed significant high-field shifts (delta up to 0.3 ppm) for the 5- and 6-proton signals compared with those of the 3-methylthio derivatives in the (1)H-NMR spectra and exhibited a definite absorption band near 425 nm in their UV spectra, indicating an intramolecular arene-arene interaction between the thieno[3,4-b]indolizine and the phenyl ring.