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Jerry L Mclaughlin - One of the best experts on this subject based on the ideXlab platform.
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asimitrin and 4 hydroxytrilobin new bioactive annonaceous acetogenins from the seeds of Asimina triloba possessing a bis tetrahydrofuran ring
Journal of Natural Products, 2005Co-Authors: Eun Joo Jung, Jerry L MclaughlinAbstract: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.
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Chemical defense in the zebra swallowtail butterfly, Eurytides marcellus, involving annonaceous acetogenins
Journal of Natural Products, 1999Co-Authors: John M. Martin, Stephen R. Madigosky, Jinn Wu, Dawei Zhou, Zhe-ming Gu, Jerry L MclaughlinAbstract: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.
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additional bioactive annonaceous acetogenins from Asimina triloba annonaceae
Bioorganic & Medicinal Chemistry, 1997Co-Authors: Kan He, Jinfeng Chao, Gengxian Zhao, Lu Zeng, Jerry L MclaughlinAbstract: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.
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three new adjacent bis tetrahydrofuran acetogenins with four hydroxyl groups from Asimina triloba
Journal of Natural Products, 1996Co-Authors: Kan He, Gengxian Zhao, Lu Zeng, Qing Ye, Karl V Wood, Jon T Schwedler, Jerry L MclaughlinAbstract: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.
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4 acetyl annonacin and 4 acetyl xylomaticin two novel bioactive mono tetrahydrofuran annonaceous acetogenins from Asimina longifolia annonaceae
Natural Product Letters, 1996Co-Authors: Qing Ye, Lu Zeng, Dean Evert, Jerry L MclaughlinAbstract:Abstract Two novel bioactive acetogenins, 4-acetyl annonacin (1) and 4-acetyl xylomaticin (2), were isolated from the leaves and twigs of Asimina longifolia K. (Annonaceae) by directing the fractionation with the brine shrimp lethality test. 1 and 2 each has a mono-tetrahydrofuran (THF) ring with two flanking hydroxyl groups and an α, β-unsaturated γ-lactone with a 4-acetoxyl. The presence of acetoxyl groups is a feature rarely found in the Annonaceous acetogenins. 1 and 2 showed potent and selective cytotoxicities among six human tumor cell lines.
J L Mclaughlin - One of the best experts on this subject based on the ideXlab platform.
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asitrilobins a and b cytotoxic mono thf annonaceous acetogenins from the seeds of Asimina triloba
Phytochemistry, 1999Co-Authors: J L MclaughlinAbstract: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.
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the absolute configuration of trilobacin and trilobin a novel highly potent acetogenin from the stem bark of Asimina triloba annonaceae
Tetrahedron, 1995Co-Authors: Gengxian Zhao, Zhe-ming Gu, Jinfeng Chao, Lu Zeng, Karl V Wood, John F Kozlowski, J L MclaughlinAbstract: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.
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parvifloracin and parviflorin cytotoxic bistetrahydrofuran acetogenins with 35 carbons from Asimina parviflora annonaceae
Canadian Journal of Chemistry, 1994Co-Authors: Sunil Ratnayake, Zhe-ming Gu, Laura R Miesbauer, David L Smith, Dean Evert, Karl V Wood, J L MclaughlinAbstract: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.
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biologically active acetogenins from stem bark of Asimina triloba
Phytochemistry, 1993Co-Authors: Gengxian Zhao, Matthew J Rieser, Laura R Miesbauer, David L Smith, J L MclaughlinAbstract:Abstract In continuing our research with cytotoxic and pesticidal components from the stem bark of the North American paw paw, Asimina triloba , the novel cytotoxic monotetrahydrofuran Annonaceous acetogenins, cis - and trans -annonacin-A-one, cis - and trans -gigantetrocinone and cis -isoannonacin, in addition to the known compounds, trans -isoannonacin and squamolone, have been identified. Brine shrimp lethality testing was used to direct the fractionation. The structures were elucidated by spectral analysis and/or chemical synthesis. These acetogenins have potent cytotoxicities against the human tumour cell lines of A-549 (lung carcinoma), MCF-7 (breast carcinoma) and HT-29 (colon adenocarcinoma).
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guinea pig maximization test of the bark extract from pawpaw Asimina triloba annonaceae
Contact Dermatitis, 1993Co-Authors: J Avalos, J L Mclaughlin, J K Rupprecht, Eloy RodriguezAbstract:Several acetogenins, characteristic of the Annonaceae, have been found to exhibit pesticidal and feeding-deterrent activities against a variety of pests and are undergoing commercial development as pesticides. The sensitizing potential of one of these plants, pawpaw. Asmina triloba Dunal, was examined in the current study. The potential of Fraction F020 (a pesticidal crude extract of pawpaw stem bark) to sensitize and elicit an allergic contact dermatitis response was determined by using a modified guinea pig maximization test (GPMT). Fraction F020 is a weak sensitizer and the active compound, asimicin, a trihydroxy-bistetrahydrofuran fatly acid γ-lactone, is a weak irritant.
Gengxian Zhao - One of the best experts on this subject based on the ideXlab platform.
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additional bioactive annonaceous acetogenins from Asimina triloba annonaceae
Bioorganic & Medicinal Chemistry, 1997Co-Authors: Kan He, Jinfeng Chao, Gengxian Zhao, Lu Zeng, Jerry L MclaughlinAbstract: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.
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three new adjacent bis tetrahydrofuran acetogenins with four hydroxyl groups from Asimina triloba
Journal of Natural Products, 1996Co-Authors: Kan He, Gengxian Zhao, Lu Zeng, Qing Ye, Karl V Wood, Jon T Schwedler, Jerry L MclaughlinAbstract: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.
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2 4 cis asimicinone and 2 4 trans asimicinone two novel bioactive ketolactone acetogenins from Asimina triloba annonaceae
Natural Toxins, 1996Co-Authors: Gengxian Zhao, Jinfeng Chao, Lu Zeng, Jerry L MclaughlinAbstract:: 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.
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the absolute configuration of adjacent bis thf acetogenins and asiminocin a novel highly potent asimicin isomer from Asimina triloba
Bioorganic & Medicinal Chemistry, 1996Co-Authors: Gengxian Zhao, Jinfeng Chao, Lu Zeng, Matthew J Rieser, Jerry L MclaughlinAbstract:Abstract A novel acetogenin, asiminocin (1), was isolated by activity-directed fractionation from the stem bark of the paw paw tree, Asimina triloba . By spectral and chemical methods, 1 was identified as (30 S )-hydroxy-4-deoxyasimicin. The absolute configuration of 1, along with those of previously reported acetogenins asimin, Asiminacin, bullatin, (30 S )-bullanin, and (30 R ) bullanin, was determined by Mosher ester methodology. Compound 1 was highly inhibitory to three human solid tumor cell lines with over a billion times the potency of adriamycin.
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longicin and goniothalamicinone novel bioactive monotetrahydrofuran acetogenins from Asimina longifolia
Journal of Natural Products, 1995Co-Authors: Quin Ye, Jerry L Mclaughlin, Gengxian Zhao, Lu Zeng, Yan Zhang, Dean EvertAbstract:: Longicin [1] and (2,4-cis and trans)-goniothalamicinone [2], two new monotetrahydrofuran Annonaceous acetogenins, have been isolated from the leaves and twigs of Asimina longifolia (the long leaf paw paw) by the use of the brine shrimp lethality test for bioactivity-directed fractionation. The structures were elucidated based on spectroscopic and chemical methods. Compound 1 was converted to its ketolactone isomer, (2,4-cis and trans)-longicinone [3], to aid the stereochemical elucidation of 1. Compounds 1-3 showed selective and potent cytotoxicities to certain human tumor cell lines, with the potency of 1 against pancreatic carcinoma (PaCa-2) over one million times that of adriamycin. Nine known cytotoxic acetogenins, annonacin, xylomaticin, isoannonacin, gigantetrocins A and B, muricatetrocins A and B, gigantetrocin-A-one and goniothalamicin, were also isolated for the first time from this species.
Lu Zeng - One of the best experts on this subject based on the ideXlab platform.
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additional bioactive annonaceous acetogenins from Asimina triloba annonaceae
Bioorganic & Medicinal Chemistry, 1997Co-Authors: Kan He, Jinfeng Chao, Gengxian Zhao, Lu Zeng, Jerry L MclaughlinAbstract: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.
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three new adjacent bis tetrahydrofuran acetogenins with four hydroxyl groups from Asimina triloba
Journal of Natural Products, 1996Co-Authors: Kan He, Gengxian Zhao, Lu Zeng, Qing Ye, Karl V Wood, Jon T Schwedler, Jerry L MclaughlinAbstract: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.
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4 acetyl annonacin and 4 acetyl xylomaticin two novel bioactive mono tetrahydrofuran annonaceous acetogenins from Asimina longifolia annonaceae
Natural Product Letters, 1996Co-Authors: Qing Ye, Lu Zeng, Dean Evert, Jerry L MclaughlinAbstract:Abstract Two novel bioactive acetogenins, 4-acetyl annonacin (1) and 4-acetyl xylomaticin (2), were isolated from the leaves and twigs of Asimina longifolia K. (Annonaceae) by directing the fractionation with the brine shrimp lethality test. 1 and 2 each has a mono-tetrahydrofuran (THF) ring with two flanking hydroxyl groups and an α, β-unsaturated γ-lactone with a 4-acetoxyl. The presence of acetoxyl groups is a feature rarely found in the Annonaceous acetogenins. 1 and 2 showed potent and selective cytotoxicities among six human tumor cell lines.
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2 4 cis asimicinone and 2 4 trans asimicinone two novel bioactive ketolactone acetogenins from Asimina triloba annonaceae
Natural Toxins, 1996Co-Authors: Gengxian Zhao, Jinfeng Chao, Lu Zeng, Jerry L MclaughlinAbstract:: 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.
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longimicins a d novel bioactive acetogenins from Asimina longifolia annonaceae and structure activity relationships of asimicin type of annonaceous acetogenins
Journal of Medicinal Chemistry, 1996Co-Authors: Qing Ye, Lu Zeng, Dean Evert, Kan He, Nicholas H Oberlies, Jerry L MclaughlinAbstract:Bioactivity-directed fractionation of the ethanol extract of Asimina longifolia led to the isolation of four novel bioactive annonaceous acetogenins: longimicins A−D (1−4). Compounds 1−4 represent the asimicin type of acetogenins; however, the locations of the adjacent bis-tetrahydrofuran (THF) ring moieties are shifted along the aliphatic chains compared to the known compounds of this type. They are the first examples among this type of acetogenins with the placements of the ring systems altered. Compounds 1−4 showed bioactivities in several bioassays, but they are less active than their structural isomers. Study of their structure−activity relationships (SAR) reveals that the position of the adjacent bis-THF ring moiety is essential for maximization of the bioactivities among these asimicin type annonaceous acetogenins.
Paul Feeny - One of the best experts on this subject based on the ideXlab platform.
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oviposition stimulant for the zebra swallowtail butterfly eurytides marcellus from the foliage of pawpaw Asimina triloba
Chemoecology, 1998Co-Authors: Meena Haribal, Paul FeenyAbstract:We have isolated a caffeoylcyclohexane-1-carboxylic acid derivative, 3-caffeoyl-muco-quinic acid (3-CmQA), as a contact oviposition stimulant for the zebra swallowtail butterfly, Eruytides marcellus (Papilionidae), from the foliage of its primary host plant, Asimina triloba (Annonaceae). This compound alone was as active in stimulating oviposition by females as were the parent ethanolic plant extract and the host plant itself. Other tested isomers of 3-CmQA, including 5-caffeoylquinic acid (5-CQA or trans-chlorogenic acid), were inactive. We found, however, that experienced female butterflies responded strongly to host volatiles, which enhanced landing rates and hence oviposition.¶ This is the first report of an oviposition stimulant for a swallowtail butterfly of the tribe Graphiini. We found 3-CmQA to be the major caffeoylcyclohexane-1-carboxylic acid isomer in plants of the genus Asimina. These plants lack appreciable amounts of 5-CQA, which has been shown previously to be one of the oviposition stimulants for certain Rutaceae- or Apiaceae-feeding swallowtails of the related tribe Papilionini.¶ Our findings, along with earlier results from the tribes Troidini and Papilionini, suggest that responses by swallowtails to hydroxycinnamic acid derivatives as oviposition cues date back at least to the ancestor of the subfamily Papilioninae.
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a caffeoylcyclohexane 1 carboxylic acid derivative from Asimina triloba
Phytochemistry, 1998Co-Authors: Meena Haribal, Paul Feeny, Cathy C LesterAbstract:Abstract Three caffeoyl derivatives of 1,3,4,5-tetrahydroxycyclohexane 1-carboxylic acid, one of them an oviposition stimulant for the zebra swallowtail butterfly, Eurytides marcellus , were isolated from Asimina triloba . The structure of the active isomer, 3-caffeoyl- muco -quinic acid, was determined by extensive NMR studies.
