Center of Chemical Innovation for Sustainability (CIS) , Mae Fah Luang University , Chiang Rai 57100 , Thailand.
School of Science , Mae Fah Luang University , Chiang Rai 57100 , Thailand.
J Nat Prod. 2019 Aug 23;82(8):2343-2348. doi: 10.1021/acs.jnatprod.9b00216. Epub 2019 Aug 12.
A chemical investigation of leaf and root extracts of led to the isolation and structural elucidation of four new prenylated isoflavones, millexatins G-J (-), and three new coumaronochromones, millexatins K-M (-), along with 16 known compounds. The structures of the new compounds were determined on the basis of NMR and MS data. Compound is a rare isoflavone having a 2-hydroxyethyl moiety at C-8, whereas the structures of compounds - formally arise from a ring closure through HO-2' and C-2. The absolute configurations at the C-2 and C-3 positions of and were determined from their ECD spectra through comparison with those of previously reported compounds. Most of compounds were evaluated for their inhibitory effects against nitric oxide (NO) production on RAW264.7 macrophages and their antibacterial activities. Compounds and inhibited NO production with IC values of 8.5 and 14.3 μM, respectively. Compounds and showed antibacterial activity against various Gram-positive bacteria with MIC values ranging from 2 to 8 μg/mL.
对 叶片和根提取物的化学研究导致了四个新的prenylated 异黄酮，millexatins G-J (-)，以及三个新的 coumaronochromones，millexatins K-M (-)，以及 16 种已知化合物的分离和结构阐明。新化合物的结构是根据 NMR 和 MS 数据确定的。化合物 是一种罕见的异黄酮，在 C-8 位具有 2-羟乙基部分，而化合物 - 的结构则是通过 HO-2'和 C-2 的环合形成的。通过与先前报道的化合物的 ECD 光谱进行比较，确定了 和 的 C-2 和 C-3 位置的绝对构型。大多数化合物都评估了它们对 RAW264.7 巨噬细胞中一氧化氮 (NO) 产生的抑制作用及其抗菌活性。化合物 和 对 NO 产生的抑制作用分别为 8.5 和 14.3 μM。化合物 和 对各种革兰氏阳性菌具有抗菌活性，MIC 值范围为 2 至 8 μg/mL。
