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A Varma - One of the best experts on this subject based on the ideXlab platform.

Ling-yi Kong - One of the best experts on this subject based on the ideXlab platform.

  • Labdane Diterpenoids from the Roots of Amomum maximum and Their Cytotoxic Evaluation
    Helvetica Chimica Acta, 2014
    Co-Authors: Ling-yi Kong
    Abstract:

    by Jian-Guang Luo, Hong Yin, Bo-Yi Fan, and Ling-Yi Kong*State Key Laboratory of Natural Medicines, Department of Natural Medicinal Chemistry,China Pharmaceutical University, 24 Tong Jia Xiang, Nanjing 210009, P. R. China(phone/fax: þ86-25-83271405; e-mail: cpu_lykong@126.com)A rare labdane diterpene g-lactam, 1, and two new labdane diterpenoids, 2 and 3, along with twoknown diterpenes, 4 and 5, were isolated from the roots of Amomum maximum. Their structures wereestablished on the basis of spectroscopic data. All of the isolates were evaluated for their cytotoxicactivities, and compound 3 was found to exhibit an inhibitory activity against MG-63 cell lines with anIC

  • diarylheptanoids from the fruits of Amomum kravanh and their inhibitory activities of nitric oxide production
    Phytochemistry Letters, 2013
    Co-Authors: Hong Yin, Jianguang Luo, Ling-yi Kong
    Abstract:

    Abstract Two new diarylheptanoids with a tetrahydropyran ring, kravanhol A (1) and kravanhol B (2), along with one known diarylheptanoid renealtin A (3) were isolated from the fruits of Amomum kravanh. The structures of compounds 1 and 2 were established by analysis of spectroscopic data and their absolute configurations were determined by Mosher's method and CD experiments. Compound 2 showed inhibitory effect on nitric oxide production in lipopolysaccharide-activated RAW264.7 macrophages with an IC50 value of 38.9 ± 1.8 μM.

  • amomaxins a and b two unprecedented rearranged labdane norditerpenoids with a nine membered ring from Amomum maximum
    Organic Letters, 2013
    Co-Authors: Siming Shan, Xiaobing Wang, Minghua Yang, Ling-yi Kong
    Abstract:

    Amomaxins A (1) and B (2), featuring an unprecedented rearranged labdane norditerpene skeleton with a nine-membered ring, along with their biosynthetic related known compound isocoronarin D (3) were isolated from the roots of Amomum maximum. Their structures with absolute configurations were determined by spectroscopic data, CD experimentation, and single-crystal X-ray diffraction. Compound 2 showed an inhibitory effect on nitric oxide (NO) production in lipopolysaccharide-induced RAW264.7 macrophages.

  • tetracyclic diterpenoids with isomerized isospongian skeleton and labdane diterpenoids from the fruits of Amomum kravanh
    Journal of Natural Products, 2013
    Co-Authors: Ling-yi Kong
    Abstract:

    Four novel diterpenoids, including three tetracyclic diterpenes with isomerized isospongian skeletons, kravanhins A–C (1–3), and kravanhin D (4), and three new labdane diterpenes (5–7) were isolated from the fruits of Amomum kravanh. Compounds 1–4 had unprecedented isospongian diterpene skeletons with a trans-anti-cis fused tricyclic ring system. The structures of compounds 1–7 were established on the basis of extensive analysis of NMR spectra, CD, and X-ray crystallography. Compound 2 showed inhibitory activity on nitric oxide production in lipopolysaccharide-induced RAW264.7 macrophages with an IC50 value of 36.2 μM.

Jingya Li - One of the best experts on this subject based on the ideXlab platform.

Isiaka A Ogunwande - One of the best experts on this subject based on the ideXlab platform.

  • essential oils constituents of the leaves of Amomum gagnepainii and Amomum repoense
    Natural Product Research, 2018
    Co-Authors: Le T Huong, Nguyen Viet Hung, Mai V Chung, Do N Dai, Isiaka A Ogunwande
    Abstract:

    The chemical constituents identified in the essential oils hydrodistilled from the leaves of Amomum gagnepainii T.L.Wu, K.Larsen and Turland and Amomum repoense Pierre ex Gagnep (Zingiberaceae) of Vietnam origin are reported. The chemical analyses were performed by means of gas chromatography-flame ionisation detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The main compounds of A. gagnepainii were farnesyl acetate (18.5%), zerumbone (16.4%) and β-caryophyllene (10.5%). On the other hand, Amomum repoense comprised of monoterpenes dominated by β-pinene (33.5%), (E)-β-ocimene (9.6%), γ-terpinene (9.1%) and α-pinene (8.4%). This is the first report on the essential oils of A. gagnepainii and A. repoense grown in Vietnam or elsewhere.

  • volatile constituents of Amomum maximum roxb and Amomum microcarpum c f liang d fang two zingiberaceae grown in vietnam
    Natural Product Research, 2015
    Co-Authors: Le T Huong, Do N Dai, Tran D Thang, Tran T Bach, Isiaka A Ogunwande
    Abstract:

    The chemical composition of essential oils obtained from the hydrodistillation of different parts of Amomum maximum Roxb and Amomum muricarpum C. F. Liang & D. Fang (Zingiberaceae) grown in Vietnam are reported. The analysis was performed by means of gas chromatography–flame ionisation detectoorand gas chromatography coupled with mass spectrometry. The major compounds identified in the oils of A. maximum were β-pinene (20.4–40.8%), α-pinene (6.8–15.0%), β-elemene (2.5–12.8%) and β-caryophyllene (2.3–10.3%). Moreover, β-phellandrene (11.6%) was present in the root oil. The main compound identified in all the oil samples of A. muricarpum was α-pinene (24.1–54.7%) and β-pinene (9.2–25.9%). In addition, limonene (7.4%) and δ-3-carene (9.4%) were present in the leaves and stem oils, respectively. However, while β-phellandrene (8.3%) could be seen prominent in the root oil, the fruits contained significant amount of zingiberene (6.3%). The largest amount of τ-muurolol (13.0%) was found in the flower oil.

Bikash Mandal - One of the best experts on this subject based on the ideXlab platform.