𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Elucidation of the stereochemistry of octahydroisoquinoline derivatives by NMR spectroscopy

✍ Scribed by Ion Ghiviriga; Patricia Q. Bottari; Tomas Hudlicky

Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
143 KB
Volume
37
Category
Article
ISSN
0749-1581

No coin nor oath required. For personal study only.

✦ Synopsis

Complete 1 H and 13 C chemical shifts assignments for 12 octahydroisoquinoline derivatives, intermediates in the synthesis of morphine, were made based on 2D NMR spectroscopy. The stereochemistry of the compounds characterized by the decahydroisoquinoline skeleton was elucidated based on the value of the 1 H-1 H vicinal coupling constants, which were measured in the phase-sensitive DQCOSY spectrum. An approach based on the pattern of the relative intensity of the cross peaks in the NOESY spectrum was taken to determine the stereochemistry of the epoxides derived from octahydroisoquinoline. A pattern of coupling constants was identified in each of the series, allowing the assignment of the epoxide relative stereochemistry by means of the proton spectrum only. For each type of stereochemistry, x-ray data of representative compounds confirmed the configuration determined by NMR.

📜 SIMILAR VOLUMES

Determination of the absolute stereochem
Determination of the absolute stereochemistry of vitamin E derived oxa-spiro compounds by NMR spectroscopy
✍ Harald Schröder; Thomas Netscher 📂 Article 📅 2001 🏛 John Wiley and Sons 🌐 English ⚖ 240 KB

## Abstract This contribution describes the structure elucidation of dimeric and trimeric oxidation products derived from natural (2__R__,4′__R__,8′__R__)‐α‐ and (2__R__,4′__R__,8′__R__)‐γ‐tocopherol, the most important lipid‐soluble vitamin E compounds and antioxidants in biological systems. Compl

Determination of the stereochemistry of
Determination of the stereochemistry of disubstituted fluoroethylenes by 13C NMR spectroscopy
✍ M. P. Bosch; F. Camps; G. Fabriàs; A. Guerrero 📂 Article 📅 1987 🏛 John Wiley and Sons 🌐 English ⚖ 335 KB

The stereochemistry of 1,Z-disubstituted fluoroethylenes, of general formula RCH,CH=CFR', has been ascertained from the different magnitudes of the upfield shift effect promoted by fluorine on the "C NMR absorptions of the underlined y-carbon of the fluorinated analogue in comparison with those of t

Assignment of stereochemistry to cyclohe
Assignment of stereochemistry to cyclohexenylidenecyanoacetates by 1H NMR spectroscopy
✍ Vassilios Bardakos; Constantine Sandris 📂 Article 📅 1981 🏛 John Wiley and Sons 🌐 English ⚖ 382 KB

## Abstract The stereochemistry of various pairs of isomeric 2‐cyclohexen‐1‐ylidenecyanoacetates was assigned using ^1^H NMR spectroscopy. The isomers with the γ‐methylene or the γ‐vinyl protons __cis__ to the carbalkoxy group were found to have the signals of these protons at approximately 0.3 ppm

NMR spectroscopic elucidation of the str
NMR spectroscopic elucidation of the structure and stereochemistry of tricyclic 3-styrylpyrazolines
✍ Gábor Tóth; András Simon; Attila Jenei; József Jekő; Albert Lévai 📂 Article 📅 2008 🏛 John Wiley and Sons 🌐 English ⚖ 130 KB

## Abstract Diastereomeric mixtures of tricyclic 3‐styrylpyrazolines have been prepared by the reaction of 3‐cynnamylidenechroman‐4‐ones and their 1‐thio analogs with hydrazine in hot acetic acid or propionic acid solutions. The diastereomeric mixtures were separated by column chromatography to obt

Structure elucidation of two diphenylhyd
Structure elucidation of two diphenylhydantoin derivatives via 1H and 13C NMR spectroscopy
✍ M. Ciechanowicz-Rutkowska; L. Ragona; F. Greco; L. Zetta; M. Pegna 📂 Article 📅 1995 🏛 John Wiley and Sons 🌐 English ⚖ 410 KB

## Abstract The solution conformations of 1‐benzyl‐5,5‐diphenyl‐2,4‐dioxo‐3‐imidazolidineacetic acid (AC) and 3‐(2,4‐dichlorobenzyl)‐5,5‐diphenyl‐2,4‐dioxo‐1‐imidazolidine acetic acid (AD) were studied by proton and carbon NMR spectroscopy. The two drugs have different pharmacological activities, A