2002
Conformational studies on indole alkaloids from Flustra foliacea by NMR and molecular modeling. Morales-Ríos Martha S., Santos-Sánchez Norma F., Suárez-Castillo Oscar R. DOI: 10.1002/mrc.1080
Abstract
1H and 13C NMR assignments for 1a4a and 1b4b were obtained using HSQC, HMBC and NOESY techniques. Differences and ambiguities from literature assignments are reconciled. For the pyrrolidine C-ring, the combined use of NMR spectroscopy and molecular mechanics calculations revealed that this ring exists in a dynamic conformational equilibrium between twist (2T1) and envelope-twist (1E1T2) conformations. In chloroform-d1, the 1H NMR coupling constants indicate that the pyrrolidine ring is biased in favor of the envelope-twist conformation. Steric requirements of the N-prenyl group enhanced the envelope-twist (1E1T2) conformation populations.
Cleavage of alkoxycarbonyl protecting groups from carbamates by t-BuNH2
Conformational studies on indole alkaloids from Flustra foliacea by NMR and molecular modeling
The absoluteconfiguration of cuauhtemone and related compounds
Role of lipid peroxidation in biliary obstruction in the rat
Absolute configuration determination of 2-(2-oxo-3-indolyl)acetamide derivatives
Synthesis of 6-bromo-2-arylindoles using 2-iodobenzoic acid as precursor
Stereochemical assignment of naturally occurring 2,3-epoxy-2-methylbutanoate esters
Synthesis of Bromoindole Alkaloids from Laurencia brongniartii
Unimolecular rearrangements of ketene-O,O-acetals and fragmentations occurring in the gas phase