Shi Zhen-Zhen, Yin Xiu-Li, Song Yin-Ping, Ji Nai-Yun
Institute of Coastal Zone Research, Chinese Academy of Sciences, 264003, Yantai, P. R. China.
Shandong Saline-Alkaline Land Modern Agriculture Company, 257345, Dongying, P. R. China.
Chem Biodivers. 2023 Oct;20(10):e202301099. doi: 10.1002/cbdv.202301099. Epub 2023 Sep 20.
One new diterpene, harziaketal A (1), and one new highly degraded sterol, trichosterol A (2), along with three known compounds, including one diterpene, harzianone (3), and two steroids, (22E,24R)-5α,6α-epoxy-ergosta-8(14),22-dien-3β,7α-diol (4) and isoergokonin B (5), were isolated from the culture of the marine-alga-epiphytic fungus Trichoderma sp. Z43 by silica gel column chromatography (CC), Sephadex LH-20 CC, and preparative thin-layer chromatography (TLC). Their structures and relative configurations were assigned by nuclear magnetic resonance (NMR) and high resolution electrospray ionisation mass spectrometry (HR-ESI-MS) data, and the absolute configuration of 1 was established by X-ray diffraction. Compound 1 features a hemiketal unit situated at the four-membered ring of harziane-type diterpenes for the first time, while 2 represents the rare occurrence of sterols with rings A and B being degraded. Compounds 1 and 2 displayed weak inhibition against the tested phytoplankton (Amphidinium carterae, Heterocapsa circularisquama, Heterosigma akashiwo, and Prorocentrum donghaiense) with half maximal inhibitory concentration (IC ) ranging from 14 to 53 μg/mL.
从海洋藻类附生真菌木霉属Trichoderma sp. Z43的培养物中，通过硅胶柱色谱（CC）、葡聚糖凝胶LH - 20柱色谱和制备薄层色谱（TLC），分离得到一个新的二萜类化合物哈齐酮A（1）、一个新的高度降解甾醇曲古甾醇A（2），以及三个已知化合物，包括一个二萜类化合物哈齐酮（3）、两个甾体化合物（22E，24R）-5α，6α-环氧-麦角甾-8（14），22-二烯-3β，7α-二醇（4）和异麦角甾菌素B（5）。通过核磁共振（NMR）和高分辨电喷雾电离质谱（HR - ESI - MS）数据确定了它们的结构和相对构型，通过X射线衍射确定了化合物1的绝对构型。化合物1首次在哈齐烷型二萜的四元环上具有一个半缩酮单元，而化合物2代表了罕见的A环和B环降解的甾醇。化合物1和2对受试浮游植物（卡氏扁藻、圆石藻、赤潮异弯藻和东海原甲藻）表现出较弱的抑制作用，半数抑制浓度（IC）范围为14至53μg/mL。
