Concise Total Synthesis of (−)-Frondosin B Using a Novel Palladium-Catalyzed Cyclization

✍ Scribed by Chambers C. Hughes; Dirk Trauner

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 34 KB
• Volume: 41
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/1521-3773(20020703)41:13<2227::aid-anie11112227>3.0.co;2-s

✦ Synopsis

In the Minireview by P. Cintas in issue 7, 2002, pp. 1139 ± 1145, the second paragraph on the right column of page 1142 may mislead some readers, as it suggests that heterochiral peptides are unable to form a helical arrangement. In fact, previous publications (see last paragraph and ref. 52 in ref. [1]) have shown that d,l peptides are capable of forming helical structures, and this fact may be of importance for understanding the development of homochirality starting from heterochiral sequences. The chiral amplification that results from the majority rule (see ref. 40 in ref. [1]) may be large enough for a small excess of majority units to initiate the epimerization of the minority units (l) to the configuration of the majority units (d). Overall, this process, after repetitive cycles, would lead to a preferential helical sense in which the predominant chirality (d) of the units that form the polypeptides is prevalent. [1, 2] This commentary should clarify the discussion of this point in the light of past and recent literature.