Biological Precursors and Genesis of Tyrian-Purple

✍ Scribed by Dr. Herbert Fouquet; Prof. Dr. Hans-Joachim Bielig Lecturer

• Book ID: 101550016
• Publisher: John Wiley and Sons
• Year: 1971
• Tongue: English
• Weight: 248 KB
• Volume: 10
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.197108161

✦ Synopsis

broad doublet, an unresolved broad signal, two poorly resolved doublets, and a very sharp doublet are observed at room temperature. This result can be simply explained on the basis of the calculated relative energies of the possible conformations of the molecule.

Introducing a methyl group at C-5 [compound ( I c ) ]

greatly alters the ratio of the conformers that differ in arrangement around N-3. We call such an indirect conformational interaction a "gear" effect. In general, this effect is found when the ratio of the conformers differing in arrangement at atom 'a' is altered by the substituents on atom 'c', the effect operating through and beyond atom 'b'. It may well contribute to an understanding of several hitherto unsolved conformational problems.