1. 2-epi-botcinin A and 3-O-acetylbotcineric acid from Botrytis cinerea
Emi Sakuno, Hiroko Tani, Hiromitsu Nakajima Biosci Biotechnol Biochem. 2007 Oct;71(10):2592-5. doi: 10.1271/bbb.70334. Epub 2007 Oct 7.
Two metabolites, 2-epi-botcinin A and 3-O-acetylbotcineric acid, were isolated from Botrytis cinerea (AEM211). The former compound was new, and the latter was known but structurally revised by us. In a test for antifungal activity against Magnaporthe grisea, a pathogen of rice blast disease, 2-epi-botcinin A was 8 times less active than botcinin A (MIC 100 microM), and the MIC value for 3-O-acetylbotcineric acid being 100 microM.
2. The Stephan Curve revisited
William H Bowen Odontology. 2013 Jan;101(1):2-8. doi: 10.1007/s10266-012-0092-z. Epub 2012 Dec 6.
The Stephan Curve has played a dominant role in caries research over the past several decades. What is so remarkable about the Stephan Curve is the plethora of interactions it illustrates and yet acid production remains the dominant focus. Using sophisticated technology, it is possible to measure pH changes in plaque; however, these observations may carry a false sense of accuracy. Recent observations have shown that there may be multiple pH values within the plaque matrix, thus emphasizing the importance of the milieu within which acid is formed. Although acid production is indeed the immediate proximate cause of tooth dissolution, the influence of alkali production within plaque has received relative scant attention. Excessive reliance on Stephan Curve leads to describing foods as "safe" if they do not lower the pH below the so-called "critical pH" at which point it is postulated enamel dissolves. Acid production is just one of many biological processes that occur within plaque when exposed to sugar. Exploration of methods to enhance alkali production could produce rich research dividends.
3. Organocatalytic asymmetric synthesis of β(3)-amino acid derivatives
Sun Min Kim, Jung Woon Yang Org Biomol Chem. 2013 Aug 7;11(29):4737-49. doi: 10.1039/c3ob40917a. Epub 2013 Jun 7.
β(3)-Amino acid derivatives are an essential resource for pharmaceutical production, medicinal chemistry, and biochemistry. In this article, recent developments in versatile organocatalysis, i.e., Brønsted acid catalysis, Brønsted base catalysis, Lewis acid catalysis, Lewis base catalysis, and phase-transfer catalysis, for the asymmetric synthesis of β(3)-amino acid derivatives will be presented.