Chemical Science Symposium 2022

Asymmetric total synthesis of (+)-propolisbenzofuran B Biswajit Sen, Mainak Bera, Saumen Hajra Centre of Biomedical Research, India

Propolis is a resinous hive product collected by honey bees from various plant sources and has also been extensively used as a health drink, in food to improve health, traditional medicine dates back at least to 300 BC, and is reported to have a broad spectrum of biological activities such as anticancer, anti-inflammatory, antibacterial, antibiotic, antioxidant, and antifungal activities. In 2000, Kadota and co-workers reported the isolation of propolisbenzofuran B (1) from the bioactivity-guided fractionation of the methanol extracts of Brazilian propolis 1 is characterized by a 1-aryl-2,3-dihydrodibenzo[b,d]furan-4(1H)-one tricyclic core. Preliminary biological data reported by the isolation chemists showed 1 to have mild cytotoxic effects on murine colon 26-L5 carcinoma cells and human HT-1080 fibrosarcoma cells. There are two reports on racemic synthesis of 1, 2 but till now no asymmetric synthesis. Here first asymmetric total synthesis of (+)-propolisbenzofuran B ( 1) and allied compounds via late-stage functionalization will be presented in the symposium.

References 1. (a) H. Banskota, Y. Tezuka, K. Midorikawa, K. Matsushige and S. Kadota, J. Nat. Prod., 2000, 63, 1277−1279; (b) A. H. Banskota, Y. Tezuka, I. K. Adnyana, E. Ishii, K. Midorikawa, K. Matsushige and S. Kadota, Phytomedicine., 2001, 8, 16−3. 2. (a) B. T. Jones, C. T. Avetta and R. J. Thomson, Chem. Sci., 2014, 5 , 1794−1798; (b) Srinivas and C. V. Ramana, Org. Lett., 2017, 19 , 6466−6469. 3. Unpublished work

P101

© The Author(s), 2022

Made with FlippingBook Learn more on our blog