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Asimina

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Jerry L Mclaughlin – 1st expert on this subject based on the ideXlab platform

  • asimitrin and 4 hydroxytrilobin new bioactive annonaceous acetogenins from the seeds of Asimina triloba possessing a bis tetrahydrofuran ring
    Journal of Natural Products, 2005
    Co-Authors: Eun Joo Jung, Jerry L Mclaughlin

    Abstract:

    Bioactivity-directed fractionation of the seeds of Asimina triloba resulted in the isolation of asimitrin (1) and 4-hydroxytrilobin (2). Compound 1 represents an adjacent ring-hydroxylated bis-tetrahydrofuran (THF) acetogenin. Compound 2 has an adjacent bis-THF ring with two flanking hydroxyl groups and a α,β-unsaturated γ-lactone with a 4-hydroxyl group. Compounds 1 and 2 showed cytotoxic selectivity, with 100−10 000 times the potency of adriamycin against prostate adenocarcinoma (PC-3) and colon adenocarcinoma (HT-29) cell lines.

  • Chemical defense in the zebra swallowtail butterfly, Eurytides marcellus, involving annonaceous acetogenins
    Journal of Natural Products, 1999
    Co-Authors: John M. Martin, Stephen R. Madigosky, Zhe-ming Gu, Dawei Zhou, Jinn Wu, Jerry L Mclaughlin

    Abstract:

    Few herbivores feed on the foliage of the North American paw paw tree, Asimina triloba; notable exceptions are the larvae of the zebra swallowtail butterfly, Eurytides marcellus. Toxic annonaceous acetogenins, produced by A. triloba, are responsible for the relative unpalatability of the leaves. Acetogenins found in A. triloba extracts are potent pesticidal and antineoplastic agents and have emetic activity in vertebrates. In this study, partitioned aqueous MeOH fractions of the bioactive CH2Cl2 extracts, of freeze-dried and pulverized larvae, and of mature butterflies revealed acetogenin content through the use of HPLC coupled to tandem MS (LC-MS/MS). This sensitive technique provides an uncomplicated method for the detection of trace compounds and, in this instance, has confirmed tissue presence of acetogenins that serve a probable role as chemical defense agents against bird predation in zebra swallowtail larvae and adults.

  • additional bioactive annonaceous acetogenins from Asimina triloba annonaceae
    Bioorganic & Medicinal Chemistry, 1997
    Co-Authors: Kan He, Jinfeng Chao, Gengxian Zhao, Lu Zeng, Jerry L Mclaughlin

    Abstract:

    Abstract Trilobalicin ( 1 ), a new nonadjacent bis-THF ring annonaceous acetogenin, 2,4- cis – ( 2 ) and 2,4- trans -trilobacinone ( 3 ), the ketolactones of trilobacin, an adjacent bis-THF ring acetogenin, were isolated from the stem bark of Asimina triloba (L.) Dunal (Annonaceae). Their structures were established based on chemical and spectral evidence. The relative stereochemistry of 1 was determined as trans/threo/threo/trans/erythro from C-10 to C-22 by comparisons of NMR data with those of model compounds. Compound 1 is the first example of a nonadjacent bis-THF acetogenin being isolated from the title species and represents a new type of these compounds. Bioactivities of these new structures against brine shrimp larvae and six human solid tumor cell lines were determined, and cytotoxic selectivities were shown for the lung (A-549) and breast (MCF-7) cell lines with up to a million times the potency of adriamycin.

J L Mclaughlin – 2nd expert on this subject based on the ideXlab platform

  • asitrilobins a and b cytotoxic mono thf annonaceous acetogenins from the seeds of Asimina triloba
    Phytochemistry, 1999
    Co-Authors: J L Mclaughlin

    Abstract:

    Abstract The seeds of Asimina triloba have yielded two novel cytotoxic mono-tetrahydrofuran (THF) Annonaceous acetogenins, asitrilobins A (1) and B (2). In addition, annonacin, asimin and Asiminacin, which are known, and annomontacin and xylomaticin, which are known but are new in this species, were obtained. Compounds 1 and 2 have a relative stereochemical relationship of erythro/cis/threo across the mono-THF ring with its two flanking hydroxyls and they, thus, represent a new type of acetogenin. Their structures were established on the basis of chemical and spectral evidence. 1 and 2 showed potent bioactivities in the brine shrimp lethality test (BST) and among six human solid tumor cell lines with notable selectivity for the pancreatic cell line (MIA PaCa-2) at ten to one-hundred times the potency of adriamycin.

  • the absolute configuration of trilobacin and trilobin a novel highly potent acetogenin from the stem bark of Asimina triloba annonaceae
    Tetrahedron, 1995
    Co-Authors: Gengxian Zhao, Zhe-ming Gu, Jinfeng Chao, Lu Zeng, Karl V Wood, John F Kozlowski, J L Mclaughlin

    Abstract:

    Abstract Trilobacin ( 1 ) is the only previously reported Annonaceous acetogenin with the erythro relative configuration between the adjacent bis-tetrahydrofuran (THF) rings. The relative configuration in the adjacent bis-THF moiety of 1 was corrected to threo/trans/erythro/cis/threo from C-15 to C-24, and the absolute configuration was determined as 4 R , 15 R , 16 R , 19 R , 20 S , 23 R , 24 R and 36 S by advanced Mosher ester methodology and the COSY and NOESY spectral analyses of its 4,24-diacetate ( 1a ). Further investigation of the EtOH extract of the stem bark of the paw paw tree, Asimina triloba , monitoring for bioactivity by brine shrimp lethality, led to a novel acetogenin, trilobin ( 2 ). Spectral and chemical methods identified 2 as a 4-deoxy-10-hydroxy isomer of 1 . The absolute configuration of 2 was determined as 10 R , 15 R , 16 R , 19 R , 20 S , 23 R , 24 R , and 36 S by analyses of its Mosher ester derivatives. 2 was selectively cytotoxic among three human solid tumor cell lines with over a billion times the potency of adriamycin.

  • parvifloracin and parviflorin cytotoxic bistetrahydrofuran acetogenins with 35 carbons from Asimina parviflora annonaceae
    Canadian Journal of Chemistry, 1994
    Co-Authors: Sunil Ratnayake, Zhe-ming Gu, Laura R Miesbauer, David L Smith, Dean Evert, Karl V Wood, J L Mclaughlin

    Abstract:

    Using lethality to brine shrimp, activity-directed fractionation of extracts of Asimina parviflora (Michx.) Dunal. (Annonaceae) has led to the isolation of two new and four known acetogenins (1–6). Compound 1, parvifloracin, is the first nonadjacent bistetrahydrofuran acetogenin with 35 carbons. Compound 2, parviflorin, is an unusual adjacent bistetrahydrofuran acetogenin with 35 carbons. Bullatacin (3), molvizarin (4), annonacin (5), and goniothalamicin (6) are also reported for the first time from this plant. Brine shrimp lethality test data and comparative cytotoxicities of 1–6 against three human solid tumor cell lines are presented.

Gengxian Zhao – 3rd expert on this subject based on the ideXlab platform

  • additional bioactive annonaceous acetogenins from Asimina triloba annonaceae
    Bioorganic & Medicinal Chemistry, 1997
    Co-Authors: Kan He, Jinfeng Chao, Gengxian Zhao, Lu Zeng, Jerry L Mclaughlin

    Abstract:

    Abstract Trilobalicin ( 1 ), a new nonadjacent bis-THF ring annonaceous acetogenin, 2,4- cis – ( 2 ) and 2,4- trans -trilobacinone ( 3 ), the ketolactones of trilobacin, an adjacent bis-THF ring acetogenin, were isolated from the stem bark of Asimina triloba (L.) Dunal (Annonaceae). Their structures were established based on chemical and spectral evidence. The relative stereochemistry of 1 was determined as trans/threo/threo/trans/erythro from C-10 to C-22 by comparisons of NMR data with those of model compounds. Compound 1 is the first example of a nonadjacent bis-THF acetogenin being isolated from the title species and represents a new type of these compounds. Bioactivities of these new structures against brine shrimp larvae and six human solid tumor cell lines were determined, and cytotoxic selectivities were shown for the lung (A-549) and breast (MCF-7) cell lines with up to a million times the potency of adriamycin.

  • three new adjacent bis tetrahydrofuran acetogenins with four hydroxyl groups from Asimina triloba
    Journal of Natural Products, 1996
    Co-Authors: Kan He, Gengxian Zhao, Lu Zeng, Qing Ye, Karl V Wood, Jon T Schwedler, Jerry L Mclaughlin

    Abstract:

    Three new adjacent bis-tetrahydrofuran ring Annonaceous acetogenins with four hydroxy groups, bullatetrocin (1), 10-hydroxyasimicin (2), and 10-hydroxytrilobacin (3), were isolated by activity-directed fractionation from the stem bark of Asimina triloba. Their structures were established on the basis of chemical and spectral evidence. The absolute stereochemistry at the C-10 hydroxy position was determined by converting 2 and 3 to their ketolactone isomers, 2,4-cis/trans 10-hydroxyasimicinones and 2,4-cis/trans 10-hydroxytrilobacinones, respectively. The bioactivities of the new compounds against brine shrimp larvae and six human solid-tumor cell lines are reported, and structure−activity relationships between trihydroxylated and tetrahydroxylated acetogenins are discussed. In addition to 1−3, gigantetrocin A, 2,4-cis/trans-gigantetrocin A-ones, annonacin, and annonacin A were also isolated for the first time from this species.

  • 2 4 cis asimicinone and 2 4 trans asimicinone two novel bioactive ketolactone acetogenins from Asimina triloba annonaceae
    Natural Toxins, 1996
    Co-Authors: Gengxian Zhao, Jinfeng Chao, Lu Zeng, Jerry L Mclaughlin

    Abstract:

    : Two novel bioactive ketolactone Annonaceous acetogenins, (2,4-cis)-asimicinone (1) and (2,4-trans)-asimicinone (2), have been isolated from Asimina triloba (Annonaceae) by bioactivity directed fractionation. The separation of these two epimeric compounds was achieved by HPLC methods using a Si gel normal phase column eluted with acetone in hexane gradients. The assignments of cis or trans stereochemistry of the ketolactone moieties were made on the bases of 1H-1H COSY and NOESY experiments. 1 and 2 showed selective cytotoxicities against A-549 (human lung cancer) and MCF-7 (human breast cancer) cell lines with ED50 values as low as < 10(-7) micrograms/ml with 2 being the more active isomer.