Caloforines A-G, coumarins from the bark of Calophyllum scriblitifolium

Ai Ogasawara; Ryo Noguchi; Takuya Shigi; Alfarius Eko Nugroho; Yusuke Hirasawa; Toshio Kaneda; Takahiro Tougan; Toshihiro Horii; A Hamid A Hadi; Hiroshi Morita

doi:10.1007/s11418-022-01613-6

Caloforines A-G, coumarins from the bark of Calophyllum scriblitifolium

J Nat Med. 2022 Jun;76(3):645-653. doi: 10.1007/s11418-022-01613-6. Epub 2022 Mar 22.

Authors

Affiliations

¹ Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41 Shinagawa-ku, Tokyo, 142-8501, Japan.
² Research Center for Infectious Disease Control, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
³ Department of Malaria Vaccine Development, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka, 565-0871, Japan.
⁴ Department of Chemistry, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.
⁵ Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41 Shinagawa-ku, Tokyo, 142-8501, Japan. [email protected].

Abstract

Bioactivity-guided separation of the methanol extract of Calophyllum scriblitifolium bark led to the isolation of five new pyranocoumarins, caloforines A-E (1-5) and two new coumarins, caloforines F and G (6 and 7). Their structures were elucidated by 1D and 2D NMR spectroscopy, and their absolute configurations were investigated by a combination of CD spectroscopy and DFT calculation. Caloforines A-F (1-6) showed moderate antimalarial activity against Plasmodium falciparum 3D7 strain.

Keywords: Antimalarial activity; Caloforines A–G; Calophyllum scriblitifolium; Coumarin; Pyranocoumarin.

MeSH terms

Antimalarials* / pharmacology
Calophyllum* / chemistry
Coumarins / chemistry
Coumarins / pharmacology
Plant Bark / chemistry
Pyranocoumarins* / analysis
Pyranocoumarins* / chemistry

Substances

Antimalarials
Coumarins
Pyranocoumarins