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  • melodinine v an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi
    Bioorganic & Medicinal Chemistry Letters, 2016
    Co-Authors: Ya-ping Liu, Tao Feng, Yun-li Zhao, Grace Gar-lee Yue, Julia Kin-ming Lee, Clara Bik-san Lau, Xiao-dong Luo
    Abstract:

    Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells.

  • Melodinine V, an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi.
    Bioorganic & Medicinal Chemistry Letters, 2016
    Co-Authors: Ya-ping Liu, Tao Feng, Yun-li Zhao, Grace Gar-lee Yue, Julia Kin-ming Lee, Clara Bik-san Lau, Xiao-dong Luo
    Abstract:

    Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells. (C) 2016 Elsevier Ltd. All rights reserved.

  • melokhanines a j bioactive monoterpenoid indole alkaloids with diverse skeletons from Melodinus khasianus
    Journal of Natural Products, 2016
    Co-Authors: Gui-guang Cheng, Afsar Khan, Lu Liu, Ya-ping Liu, Xiao-dong Luo, Paul-keilah Lunga, Bo Hou, Ying-ying Chen, Zhili Zuo
    Abstract:

    The new melokhanines A–J (1–10) and 22 known (11–32) alkaloids were isolated from the twigs and leaves of Melodinus khasianus. The new compounds and their absolute configurations were elucidated by extensive analysis of spectroscopic, X-ray diffraction, and computational data. Melokhanine A (1), composed of a hydroxyindolinone linked to an octahydrofuro[2,3-b]pyridine moiety, is an unprecedented monoterpenoid indole alkaloid. Melokhanines B–H (2–8) possess a new 6/5/5/6/6 pentacyclic indole alkaloid skeleton. Alkaloids 1–16, 25–27, 31, and 32 showed the best antibacterial activity against Pseudomonas aeruginosa (MIC range 2–22 μM). Among the seven dermatophytes tested, compound 1 showed significant inhibitory activity against Microsporum canis, M. ferrugineum, and Trichophyton ajelloi (MIC range 38–150 μM), i.e., half the efficacy of the positive control, griseofulvin.

  • Antibacterial constituents from Melodinus suaveolens.
    Chinese Journal of Natural Medicines, 2015
    Co-Authors: Paul-keilah Lunga, Ya-ping Liu, Yun-li Zhao, Xu-jie Qin, Xing-wei Yang, Xiao-dong Luo
    Abstract:

    To investigate the non-alkaloidal chemical constituents of the stems and leaves of Melodinus suaveolens and their antibacterial activities. Compounds were isolated and purified by repeated silica gel, Sephadex LH-20, RP18, and preparative HPLC. Their structures were elucidated by comparison with published spectroscopic data, as well as on the basis of extensive spectroscopic analysis. The antibacterial screening assays were performed by the dilution method. Fourteen compounds were isolated, and identified as lycopersene (1). betulinic aldehyde (2), 3 beta-acctoxy-22,23,24,25,26,27-hexanordammaran-20-one(3), 3a-acetyl-2, 3, 5-trimethyl-7a-hydroxy-5-(4,8, 12-trimethyl-tridecanyl)-1,3a, 5,6,7,7a-hexahydro- 4-oxainden-1-one (4), 3 beta-hydroxy-28-norlup-20(29)-ene-17 beta-hydroperoxide (5), 3 beta-hydroxy-28-norlup-20(29)-ene-17 alpha-hydroperoxide (6), beta-sitosterol (7), 28-nor-urs-12-ene-3 beta, 17 beta-diol (8), alpha-amyrin (9), ergosta-4,6,8(14) 22-tetraen-3-one (10), 3 beta-hydroxy-urs-11-en-28,13 beta-olide (11), betulin (12), obtusalin (13), and ursolic acid (14), Among the isolates,. compounds 1, 2. 6, 8, 10, and 14 showed potent antibacterial activities against the four bacteria, This is the first report of the antibacterial activity of the constituents of Melodinus suaveolens

  • Melosuavines A-H, Cytotoxic Bisindole Alkaloid Derivatives from Melodinus suaveolens
    Journal of Natural Products, 2013
    Co-Authors: Ya-ping Liu, Gui-guang Cheng, Xiang-hai Cai, Tao Feng, Yun-li Zhao, Bao-hong Zhang, Xiao-dong Luo
    Abstract:

    Eight new bisindole alkaloids, melosuavines A C (1-3), having an aspidosperma-scandine linkage, melosuavines D F (4-6), possessing an aspidosperma-aspidosperma skeleton, and melosuavines G and H (7 and 8) of the aspidosperma-venalatonine type, tenuicausine (9), and melodinine J (10) were isolated from the twigs and leaves of Melodinus suaveolens. The structures of 1-8 were elucidated by extensive spectroscopic methods, and compounds 9 and 10 were identified by comparison with data in the literature. The relative configuration 9 was determined from the ROESY spectrum, and some NMR signals were reassigned. Compounds 1, 2, 4-6, 8, and 10 exhibited low micromolar cytotoxicity against one or more of five human cancer cell lines.

Ya-ping Liu - One of the best experts on this subject based on the ideXlab platform.

  • chemical constituents from Melodinus cochinchinensis lour merr and their chemotaxonomic significance
    Biochemical Systematics and Ecology, 2021
    Co-Authors: Lin Yang, Ya-ping Liu, Xiaoyan Cui, Bei Wang
    Abstract:

    Abstract A phytochemical investigation on the twigs and leaves of Melodinus cochinchinensis (Lour.) Merr. resulted in the isolation and identification of 22 compounds, including seven sesamin-type lignans (1–7), three pentacyclic triterpenes (8–10), one anthraquinone (11), one flavanone (12), two phenolic compounds (13 and 14), five aspidosperma-type indole alkaloids (15–19), and three eburnan-type indole alkaloids (20–22). The structures of these compounds were elucidated by means of spectroscopic analysis, including HREIMS together with 1D and 2D NMR experiments, and comparison with reported data. Among them, compounds 1/4, 2/5, and 3/6 are three pairs epimers at C-7''. Compounds 1–6, 8 and 11 were firstly isolated from the family Apocynaceae, whereas 17 was isolated from Melodinus species for the first time. Compound 8 was only found in Juglans hopeiensis, while 11 was only found in roots of Rubia cordifolia. Compounds 1–6, 8, 11 and 15–22 could be considered as chemotaxonomic markers for M. cochinchinensis. Furthermore, the chemotaxonomic significance and distribution of these isolates in Melodinus genus are discussed in detail.

  • Potent immunosuppressive and anti-inflammatory bisindole alkaloids from Melodinus fusiformis.
    Natural product research, 2021
    Co-Authors: Lu Liu, Jin-tang Wang, Afsar Khan, Jian-xin Cao, Gui-guang Cheng, Ya-ping Liu, Ming-jun Xie, Wen-bing Zhou, Jia-yi Wang, Wen-yuan Mao
    Abstract:

    Phytochemical investigation of Melodinus fusiformis led to a new aspidosperma-aspidosperma bisindole alkaloid (BIA), bis-19β-hydroxyvenalstonidine (1), together with three known BIAs (2–4). The str...

  • hresims guided isolation of aspidosperma scandine type bisindole alkaloids from Melodinus cochinchinensis and their anti inflammatory and cytotoxic activities
    Phytochemistry, 2021
    Co-Authors: Lu Liu, Jin-tang Wang, Afsar Khan, Ya-ping Liu, Xu-jie Qin, Yudan Wang, Meilian Yang, Gui-guang Cheng
    Abstract:

    Abstract The Melodinus species have been proved to be good resources of bisindole alkaloids. Six bisindole alkaloids were isolated from the leaves and stems of Melodinus cochinchinensis (Lour.) Merr. guided by HRESIMS data analysis. Among them, melokhanines K-M, epi-scandomelonine, and epi-scandomeline possessed aspidosperma-scandine skeleton linked by a C–C bond while meloyine II had a scandine-scandine skeleton. The structures were established by extensive spectroscopic analysis of their HRESIMS and NMR data. Melokhanines K-M were undescribed compounds, while epi-scandomelonine, epi-scandomeline and meloyine II were known compounds, which were reported from Melodinus species for the first time. The anti-inflammatory and cytotoxic activities of the isolates were also evaluated in vitro. Melokhanine K and meloyine II showed potent inhibitory activity on the production of nitric oxide, interleukin-6, and tumor necrosis factor-α in LPS-induced RAW 264.7 macrophages, whereas epi-scandomelonine and epi-scandomeline exhibited certain cytotoxic activity against MOLT-4 cells with IC50 values 5.2 and 1.5 μM, respectively.

  • Targeted isolation of terpenoid indole alkaloids from Melodinus cochinchinensis (Lour.) Merr. using molecular networking and their biological activities
    Industrial Crops and Products, 2020
    Co-Authors: Yudan Wang, Afsar Khan, Lu Liu, Ya-ping Liu, He Shuyue, Qingwang Xue, Qi-min Cui, Gui-guang Cheng
    Abstract:

    Abstract Melodinus cochinchinensis (Lour.) Merr. has been used in Traditional Chinese Medicine for the management of various ailments, yet its chemical constituents are rarely studied. This study was aimed to isolate terpenoid indole alkaloids (TIAs) from the aerial parts of M. cochinchinensis by the guidance of ultrahigh-performance liquid chromatography coupled with a tandem mass spectrometry (UHPLC-MS/MS), and to elucidate their cytotoxic, immunosuppressive and anti-inflammatory activities. Eight new TIAs (1 and 5-11) along with 21 previously described analogues were isolated with the basis of molecular networking developed by our previously reported TIAs from the species of Melodinus. The structures of new TIAs were elucidated by the analysis of extensive spectroscopic data. Among the tested isolates, 11-methoxytabersonine (25) exhibited considerable cytotoxic activity against human acute lymphoblastic leukemia (MOLT-4), breast adenocarcinoma (MCF-7), pro-myeloid leukemia (HL-60), lung adenocarcinoma (A-549), and hepatocelluar carcinoma (SMMC-7721) cell lines, which was more effective than the positive control, cisplatin. The 19β-hydroxyvenalstonidine (21) displayed moderate immunosuppressive effect against Con A-induced splenocyte proliferation at 40 μM, while 16,17-dehydro-19S-vindolinine (1) showed potent inhibitory activity on nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) expressions in LPS-induced RAW 264.7 macrophages.

  • melodinine v an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi
    Bioorganic & Medicinal Chemistry Letters, 2016
    Co-Authors: Ya-ping Liu, Tao Feng, Yun-li Zhao, Grace Gar-lee Yue, Julia Kin-ming Lee, Clara Bik-san Lau, Xiao-dong Luo
    Abstract:

    Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells.

Brian M. Stoltz - One of the best experts on this subject based on the ideXlab platform.

Gui-guang Cheng - One of the best experts on this subject based on the ideXlab platform.

  • Potent immunosuppressive and anti-inflammatory bisindole alkaloids from Melodinus fusiformis.
    Natural product research, 2021
    Co-Authors: Lu Liu, Jin-tang Wang, Afsar Khan, Jian-xin Cao, Gui-guang Cheng, Ya-ping Liu, Ming-jun Xie, Wen-bing Zhou, Jia-yi Wang, Wen-yuan Mao
    Abstract:

    Phytochemical investigation of Melodinus fusiformis led to a new aspidosperma-aspidosperma bisindole alkaloid (BIA), bis-19β-hydroxyvenalstonidine (1), together with three known BIAs (2–4). The str...

  • hresims guided isolation of aspidosperma scandine type bisindole alkaloids from Melodinus cochinchinensis and their anti inflammatory and cytotoxic activities
    Phytochemistry, 2021
    Co-Authors: Lu Liu, Jin-tang Wang, Afsar Khan, Ya-ping Liu, Xu-jie Qin, Yudan Wang, Meilian Yang, Gui-guang Cheng
    Abstract:

    Abstract The Melodinus species have been proved to be good resources of bisindole alkaloids. Six bisindole alkaloids were isolated from the leaves and stems of Melodinus cochinchinensis (Lour.) Merr. guided by HRESIMS data analysis. Among them, melokhanines K-M, epi-scandomelonine, and epi-scandomeline possessed aspidosperma-scandine skeleton linked by a C–C bond while meloyine II had a scandine-scandine skeleton. The structures were established by extensive spectroscopic analysis of their HRESIMS and NMR data. Melokhanines K-M were undescribed compounds, while epi-scandomelonine, epi-scandomeline and meloyine II were known compounds, which were reported from Melodinus species for the first time. The anti-inflammatory and cytotoxic activities of the isolates were also evaluated in vitro. Melokhanine K and meloyine II showed potent inhibitory activity on the production of nitric oxide, interleukin-6, and tumor necrosis factor-α in LPS-induced RAW 264.7 macrophages, whereas epi-scandomelonine and epi-scandomeline exhibited certain cytotoxic activity against MOLT-4 cells with IC50 values 5.2 and 1.5 μM, respectively.

  • Targeted isolation of terpenoid indole alkaloids from Melodinus cochinchinensis (Lour.) Merr. using molecular networking and their biological activities
    Industrial Crops and Products, 2020
    Co-Authors: Yudan Wang, Afsar Khan, Lu Liu, Ya-ping Liu, He Shuyue, Qingwang Xue, Qi-min Cui, Gui-guang Cheng
    Abstract:

    Abstract Melodinus cochinchinensis (Lour.) Merr. has been used in Traditional Chinese Medicine for the management of various ailments, yet its chemical constituents are rarely studied. This study was aimed to isolate terpenoid indole alkaloids (TIAs) from the aerial parts of M. cochinchinensis by the guidance of ultrahigh-performance liquid chromatography coupled with a tandem mass spectrometry (UHPLC-MS/MS), and to elucidate their cytotoxic, immunosuppressive and anti-inflammatory activities. Eight new TIAs (1 and 5-11) along with 21 previously described analogues were isolated with the basis of molecular networking developed by our previously reported TIAs from the species of Melodinus. The structures of new TIAs were elucidated by the analysis of extensive spectroscopic data. Among the tested isolates, 11-methoxytabersonine (25) exhibited considerable cytotoxic activity against human acute lymphoblastic leukemia (MOLT-4), breast adenocarcinoma (MCF-7), pro-myeloid leukemia (HL-60), lung adenocarcinoma (A-549), and hepatocelluar carcinoma (SMMC-7721) cell lines, which was more effective than the positive control, cisplatin. The 19β-hydroxyvenalstonidine (21) displayed moderate immunosuppressive effect against Con A-induced splenocyte proliferation at 40 μM, while 16,17-dehydro-19S-vindolinine (1) showed potent inhibitory activity on nitric oxide (NO), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) expressions in LPS-induced RAW 264.7 macrophages.

  • Chemical constituents of Melodinus hemsleyanus diels
    Biochemical Systematics and Ecology, 2019
    Co-Authors: Jin-tang Wang, Li-wen Liang, Afsar Khan, Lu Liu, Jian-xin Cao, Gui-guang Cheng, Tian-rui Zhao
    Abstract:

    Abstract Phytochemical investigation on the aerial parts of Melodinus hemsleyanus diels (Jahrb, Syst, 1995) led to the isolation and identification of 27 compounds, including fifteen aspidosperma-type alkaloids (1–15), four quinoline-type alkaloids (16–19), three quebrachamine-type alkaloids (20–22), and five eburna-type alkaloids (23–27). The structure of compound 1 was elucidated by means of spectroscopic analysis, including HRESIMS, and 1D and 2D NMR experiments. Compounds 1–2, 6, 10, 12, 13, 15, 16 and 20–27 are herein reported for the first time from the studied plant, while the compounds 1–2 and 21 have not previously been recorded in the genus Melodinus. The aspidosperma-type monoterpenoid indole alkaloids in M. hemsleyanus could serve as chemotaxonomic markers.

  • melokhanines a j bioactive monoterpenoid indole alkaloids with diverse skeletons from Melodinus khasianus
    Journal of Natural Products, 2016
    Co-Authors: Gui-guang Cheng, Afsar Khan, Lu Liu, Ya-ping Liu, Xiao-dong Luo, Paul-keilah Lunga, Bo Hou, Ying-ying Chen, Zhili Zuo
    Abstract:

    The new melokhanines A–J (1–10) and 22 known (11–32) alkaloids were isolated from the twigs and leaves of Melodinus khasianus. The new compounds and their absolute configurations were elucidated by extensive analysis of spectroscopic, X-ray diffraction, and computational data. Melokhanine A (1), composed of a hydroxyindolinone linked to an octahydrofuro[2,3-b]pyridine moiety, is an unprecedented monoterpenoid indole alkaloid. Melokhanines B–H (2–8) possess a new 6/5/5/6/6 pentacyclic indole alkaloid skeleton. Alkaloids 1–16, 25–27, 31, and 32 showed the best antibacterial activity against Pseudomonas aeruginosa (MIC range 2–22 μM). Among the seven dermatophytes tested, compound 1 showed significant inhibitory activity against Microsporum canis, M. ferrugineum, and Trichophyton ajelloi (MIC range 38–150 μM), i.e., half the efficacy of the positive control, griseofulvin.

Tao Feng - One of the best experts on this subject based on the ideXlab platform.

  • melodinines y1 y4 four monoterpene indole alkaloids from Melodinus henryi
    RSC Advances, 2021
    Co-Authors: Fa-lei Zhang, Tao Feng, Ji-kai Liu
    Abstract:

    Melodinines Y1–Y4 (1–4), four undescribed alkaloids were isolated from Melodinus henryi. Their structures were elucidated by extensive NMR, mass spectroscopic analyses, theoretical NMR and electronic circular dichroism (ECD) calculations. Compounds 1 and 2 are the first examples of bisindole alkaloids possessing an eburnamine–leuconoxine combination. Compound 3 is a rare 2,3-seco pleiocarpamine type monoterpene indole alkaloid. Compound 1 showed cytotoxic activities against six human cancer cell lines with IC50 values of 0.5–15.2 μM.

  • Monoterpenoid indole alkaloids from the fruits of Melodinus henryi
    Phytochemistry Letters, 2020
    Co-Authors: Qian Shao, Fa-lei Zhang, Tao Feng, Ji-kai Liu
    Abstract:

    Abstract Four undescribed monoterpenoid indole alkaloids, melodinines X1‒X4 (1‒4), together with fourteen known ones, have been isolated from the fruits of Melodinus henryi. Their structures with absolute configurations were elucidated by extensive spectroscopic methods and ECD calculations. Compound 1 shows a significant cytotoxicity to HL-60 cancer cell line with an IC50 value of 0.8 μM.

  • Monoterpenoid indole alkaloids from the bark of Melodinus henryi.
    Fitoterapia, 2019
    Co-Authors: Fa-lei Zhang, Qian Shao, Tao Feng, Hui-xiang Yang, Ji-kai Liu
    Abstract:

    Abstract Four new alkaloids, melodinines W1–W4 (1–4), together with twenty one known alkaloids (5–25) were isolated from Melodinus henryi. The structures with absolute configurations were elucidated by extensive MS and NMR spectroscopic methods, as well as the single crystal X-ray diffraction and ECD calculations. All compounds were evaluated for their cytotoxicities to five human cancer cell lines. Many compounds showed certain cytotoxicities to five human cancer cell lines with an IC50 range of 1.4–29.4 μM.

  • melodinine v an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi
    Bioorganic & Medicinal Chemistry Letters, 2016
    Co-Authors: Ya-ping Liu, Tao Feng, Yun-li Zhao, Grace Gar-lee Yue, Julia Kin-ming Lee, Clara Bik-san Lau, Xiao-dong Luo
    Abstract:

    Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells.

  • Melodinine V, an antitumor bisindole alkaloid with selective cytotoxicity from Melodinus henryi.
    Bioorganic & Medicinal Chemistry Letters, 2016
    Co-Authors: Ya-ping Liu, Tao Feng, Yun-li Zhao, Grace Gar-lee Yue, Julia Kin-ming Lee, Clara Bik-san Lau, Xiao-dong Luo
    Abstract:

    Melodinine V (1) with a vincanol-eburenine skeleton, was isolated from Melodinus henryi. The structure was elucidated by extensive spectroscopic methods and further confirmed by the single crystal X-ray diffraction analysis. Melodinine V showed selective cytotoxic activities against human colon cancer cell line HT-29 and inhibited cell proliferation in a concentration-dependent manner. It induced cell cycle arrest at G1 phase and cellular apoptosis by increasing histone-associated DNA fragmentation in the treated HT-29 cells. (C) 2016 Elsevier Ltd. All rights reserved.