Two new phenolic compounds, caesalpiniaphenols G-H (1 and 2), were isolated from Vietnamese Caesalpinia sappan heartwood. The chemical structures were established mainly by extensive spectroscopic studies and chemical evidence. Compounds 1 and 2 showed potent inhibitory activity against HL-60 cancer cell lines with respective IC50 values of 16.7 and 22.5 µg/mL. Treating HL-60 cells with various concentrations of 1 resulted in growth inhibition and the induction of apoptosis.

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From the stem barks of Swintonia griffithii, six flavonoids: (–)‐naringenin (1), (–)‐eriodictyol (2), (+)‐taxifolin (3), (–)‐butin (4), (–)‐fustin (5), and 3′,4′,7‐trihydroxyflavone (6) were isolated. Their structures were determined based on the spectroscopic interpretation and compared with those of reported data. In the tyrosinase inhibitory activity test, (+)‐taxifolin (3) and 3′,4′,7‐trihydroxyflavone (6) exhibited potent effect with the IC50 values of 20.9 and 56.7 μM, respectively.

Six lupan-type triterpenoids: 29-norlupan-3,20-dione (1), 3β-hydroxy-29-norlupan-20-one (2), betulonic acid (3), salacianol (4), 30-hydroxylup-20(29)-en-3-one (5), and lup-20(29)-ene-3β,30-diol (6) have been isolated from the CHCl3-soluble fraction of the stem of Salacia chinensis L. (Celastraceae). Their chemical structures were elucidated based on the NMR spectroscopic analysis and comparison with the literatures. Compounds (5) and (6) showed very weak α-glucosidase inhibitory activity with the IC50 values of 211.5 and 246.8 M, respectively.

Solanum procumbens L. is a medicinal plant belonging to the Solanaceae family. In Vietnam, it is known as "Ca gai leo", and it cultivated in some tropical countries in China, Laos, Cambodia, and Vietnam. From the stem of the ethyl acetate extract of Solanum procumbens, we had isolated one anthraquinone (1), four polyphenols (2-5), and one indole (6). By spectroscopic methods as well as comparing with data in the literature, their chemical structures were elucidated as ziganein (1), benzoic acid (2), salicylic acid (3), 4-hydroxybenzaldehyde (4), vanillic acid (5), and indole-3-carbaldehyde (6). These compounds were isolated for the first time from the genus Solanum.

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Swintonia floribunda Griff. is an evergreen tree that belongs to Anacardiaceae family, which grows at Tay Nguyen, Lam Dong, and Dong Nai Provinces in Vietnam. Swintonia floribunda showed many interesting biological activities such as antitumor effect against breast and pancreatic cancers, antioxidant, and antimicrobial activities. From the stem barks of Swintonia floribunda Griff. (Anacardiaceae) collected in Dong Nai province, three epoxylignans: pinoresinol (1), syringaresinol (2), epipinoresinol (3), together with three other compounds: n-heptacosyl trans-ferulate (4), methyl orsellinate (5), and friedelin (6) have been isolated from the EtOAc-soluble extract. The chemical structure of these compounds were determined by 1D and 2D NMR spectra and comparison with published data. These compounds were first reported in Swintonia floribunda

Bài báo đề xuất phương pháp tính toán tối ưu việc lắp đặt các máy phát phân tán (DG) trong lưới điện phân phối nhằm giảm tổn thất dựa trên sự kết hợp giữa kỹ thuật phân tích tiếp cận và xấp xỉ tốn thất. Phương pháp đề xuất được kiểm chứng trên hai lưới điện phân phối IEEE chuẩn. Kết quả đạt được của phương pháp đề xuất được so sánh với phương pháp hệ số độ nhạy tổn thất (LFS) để thấy tính hiệu quả.