Rare prenylated isoflavonoids from the young twigs of Millettia extensa and their cytotoxic activities

Sarot Cheenpracha; Ratchanaporn Chokchaisiri; Surat Laphookhieo; Thunwadee Limtharakul; Chutamas Thepmalee

doi:10.1039/d2ra05950a

Rare prenylated isoflavonoids from the young twigs of Millettia extensa and their cytotoxic activities

RSC Adv. 2022 Oct 24;12(47):30359-30364. doi: 10.1039/d2ra05950a.

Authors

Sarot Cheenpracha¹, Ratchanaporn Chokchaisiri¹, Surat Laphookhieo^{2

3}, Thunwadee Limtharakul⁴, Chutamas Thepmalee⁵

Affiliations

¹ Division of Chemistry, School of Science, University of Phayao Phayao 56000 Thailand cheenpracha@gmail.com sarot.ch@up.ac.th.
² Center of Chemical Innovation for Sustainability (CIS), School of Science, Mae Fah Luang University Chiang Rai 57100 Thailand.
³ Medicinal Plants Innovation Center of Mae Fah Luang University Chiang Rai 57100 Thailand.
⁴ Department of Chemistry, Center of Excellence for Innovation in Chemistry, Faculty of Science, The Graduate School and Research Center on Chemistry for Development of Health Promoting Products from Northern Resources, Chiang Mai University Chiang Mai 50200 Thailand.
⁵ Division of Biochemistry, School of Medical Sciences, University of Phayao Phayao 56000 Thailand.

Abstract

Three new isoflavonoids, millexatins N-P (1-3), along with seven known compounds (6-10), were isolated from the acetone extract of the young twigs of Millettia extensa. The structures were characterized by NMR spectroscopic and mass spectrometric analyses. Millexatin N (1) is an unusual geminal diisoprenylated isoflavone with a modified ring A. Millexatin P (3) is an unusual isoflavone with a cyclohexyl substituent on ring B, which is extremely rare in nature. The isolated metabolites (1, 2, and 6-10) were evaluated for cytotoxicities against MDA-MB231, Huh-7, KKU-100 and normal human dermal fibroblast (NHDF) cell lines. Only compounds 1, 6 and 8 showed cytotoxicities against all cell lines with IC₅₀ values ranging from 13.9 to 30.9 μM.