Major research fields
Synthetic Organic Chemistry, Natural Product Chemistry
Synthetic organic chemistry in the fields of carbohydrates, natural products, and developments of new reactions are studied in our laboratory. For the carbohydrate synthesis, we are focusing on developing new methodologies for complete stereoselectivity in glycosylation reactions. For this purpose, we have ignored the classical method such as the neighboring group participation, but enthused about the realization of the stereoselectivity utilizing conformational restriction of sugars. For the natural products synthesis, ellagitannins are ourrecent synthetic targets. Ellagitannins are a structurally and biologically diverse class of hydrolysable tannins. Most of ellagitannins have been reported to possess diverse biological activities such as antiviral, antimicrobial, and antitumor activities. Structurally, ellagitannin often includes compounds that possess glucose in axial-rich conformation. We have achieved the first total synthesis of such axial-rich ellagitannins, while studying for more complex compounds. To achieve the developments of new glycosylation reactions and total syntheses of complex ellagitannins, we often realize the needs for new transformations of organic compounds. Tackling the needs can provide new reactions.
Major relevant publications
- Total Synthesis of (+)-Davidiin, Kasai, Y.; Michihata, N.; Nishimura. H.; Hirokane, T.; Yamada, H. Angew. Chem. Int. Ed. 2012, 51, 8026–8029. Highlighted in Synfacts 2012, 8, 1062.
- Completely β-Selective Glycosylation Using 3,6-O-(O-Xylylene)-Bridged Axial-Rich Glucosyl Fluoride. Okada, Y.; Asakura, N.; Bando, M.; Ashikaga, Y.; Yamada, H. J. Am. Chem. Soc. 2012, 134, 6940–6943.
- Total Synthesis of (–)-Corilagin. Yamada, H.; Nagao, K.; Dokei, K.; Kasai, Y.; Michihata, N. J. Am. Chem. Soc. 2008, 130, 7566–7567. Highlighted in Synfacts 2009, 5.