Pawinee Piyachaturawat - Academia.edu (original) (raw)
Papers by Pawinee Piyachaturawat
Phytochemistry, 2020
The chemical study on the heartwoods extract of Ventilago harmandiana (Rhamnaceae) resulted in th... more The chemical study on the heartwoods extract of Ventilago harmandiana (Rhamnaceae) resulted in the isolation of ten previously undescribed pyranonaphthoquinones (ventilanones A−J), an undescribed anthraquinone (ventilanone K), together with eight known anthraquinone derivatives. Their structures were elucidated by extensive analysis of their spectroscopic data. The absolute configuration of ventilanone A was established from single crystal X-ray crystallographic analysis of its p-bromobenzenesulfonate ester derivative using Cu Kα radiation. The absolute configurations of the other related compounds were identified by comparison of their ECD data with those of ventilanone A and related known compounds. Cytotoxic and anti-inflammatory activities of some of the isolated compounds were evaluated. Ventilanone A and ventilanone C exhibited moderate cytotoxicity against P-388 cell line. Ventilanone D exhibited significant anti-inflammatory activity while ventilanone A and ventilanone C showed moderate activity.
Scientific Reports, 2018
The Wnt/β-catenin signaling pathway plays a key role in the progression of human colorectal cance... more The Wnt/β-catenin signaling pathway plays a key role in the progression of human colorectal cancers (CRCs) and is one of the leading targets of chemotherapy agents developed for CRC. The present study aimed to investigate the anti-cancer effects and molecular mechanisms of 19-O-triphenylmethyl andrographolide (RS-PP-050), an andrographolide analogue and determine its activity in the Wnt/β-catenin pathway. RS-PP-050 was found to potently inhibit the proliferation and survival of HT-29 CRC cells. It induces cell cycle arrest and promotes apoptotic cell death which was associated with the activation of PARP-1 and p53. Furthermore, RS-PP-050 exerts inhibitory effects on β-catenin transcription by suppressing T-cell factor/lymphocyte enhancer factor (TCF/LEF) activity in cells overexpressing β-catenin and by down-regulating the endogenous expression of Wnt target genes. RS-PP-050 also decreased the protein expression of the active form of β-catenin but functions independently of GSK-3β, ...
Introduction. Currently, a number of semi-synthetic of natural plant compounds have been develope... more Introduction. Currently, a number of semi-synthetic of natural plant compounds have been developed to improve its effectiveness for treatment of cancers. In the present study, we investigated the anti-proliferative activity and apoptosis induction of MUC-30 in human breast cancer cells (MCF-7). MUC-30, a semi- synthetic analog of lignan, isolated from Phyllanthus taxodiifolius Beille (Krai Hang Nak). Methods. MCF-7 cells were treated with various concentrations of MUC-30 (0.01-10 µM) for 24-72 h and cell viability was evaluated by MTT assay. The anti-proliferative effect of the compound to MCF-7 cells via apoptosis pathway was determined by using DAPI assay, flow cytometry analysis, and the protein expression of PARP-1. Results. MUC-30 potently inhibited the proliferation of MCF-7 cells in a concentration- and time-related manners. Its IC50 (concentration that inhibits 50% of cell growth) was approximately 0.23 ± 0.07 µM at 72 h. The compound induced morphological changes of nucleus...
Phytochemistry Letters, 2020
Natural Product Communications, 2014
Bioassay-guided fractionation of the cytotoxic ethyl acetate fraction of the sequential methanol ... more Bioassay-guided fractionation of the cytotoxic ethyl acetate fraction of the sequential methanol extract from the leaves and twigs of Dasymaschalon sootepense led to the isolation of a new 7-hydroxy aporphine alkaloid, 6a,7-dehydrodasymachaline (1) along with the five known compounds (-)-nordicentrine (2), dicentrinone (3), (-)-sinactine (4), aristolactam AII (5) and epiberberine (6). Their structures were elucidated by spectroscopic methods. This is the first report of alkaloids 1–2 and 5–6 from the genus Dasymaschalon. Compounds 1 and 5 showed cytotoxicity against a panel of cancer cell lines.
Biomedicine & Pharmacotherapy, 2018
Hyperactivation of Wnt/β-catenin signaling implicated in oncogenesis of colorectal cancer (CRC) i... more Hyperactivation of Wnt/β-catenin signaling implicated in oncogenesis of colorectal cancer (CRC) is a potential molecular target for chemotherapy. An andrographolide analogue, 3A.1 (19-tert-butyldiphenylsilyl-8, 17-epoxy andrographolide) has previously been reported to be potently cytotoxic toward cancer cells by unknown molecular mechanisms. The present study explored the anti-cancer activity of analogue 3A.1 on Wnt/β-catenin signaling in colon cancer cells (HT29 cells) which were more sensitive to the others (HCT116 and SW480 cells). Analogue 3A.1 inhibited viability of HT29 cells with IC 50 value of 11.1 ± 1.4 μM at 24 h, which was more potent than that of the parent andrographolide. Analogue 3A.1 also suppressed the proliferation of HT29 cells and induced cell apoptosis in a dose-dependent manner. Its apoptotic activity was accompanied with increased expressions of proteins related to DNA damages; PARP-1 and γ-H2AX. In addition, analogue 3A.1 significantly inhibited T-cell factor and lymphoid enhancer factor (TCF/LEF) promoter activity of Wnt/β-catenin signaling. Accordingly, the expressions of Wnt target genes and β-catenin protein were suppressed. Moreover, analogue 3A.1 increased the activity of GSK-3β kinase, which is a negative regulator responsible for degradation of intracellular β-catenin. This mode of action was further supported by the absence of the effects after treatment with a GSK-3β inhibitor, and over-expression of a mutant β-catenin (S33Y). Our findings reveal, for the first time, an insight into the molecular mechanism of the anti-cancer activity of analogue 3A.1 through the inhibition of Wnt/β-catenin/GSK-3β pathway and provide a therapeutic potential of the andrographolide analogue 3A.1 in CRC treatment.
Organic Chemistry Frontiers, 2018
Secopaxilline A, featuring a C–N cleavage of an indole-diterpenoid skeleton, was isolated from Pe... more Secopaxilline A, featuring a C–N cleavage of an indole-diterpenoid skeleton, was isolated from Penicillium camemberti and synthesized from paxilline.
Investigational New Drugs, 2012
Topoisomerase II α enzyme plays a critical role in DNA replication process. It controls the topol... more Topoisomerase II α enzyme plays a critical role in DNA replication process. It controls the topologic states of DNA during transcription and is essential for cell proliferation. Human DNA topoisomerase II α (hTopo II α) is a promising chemotherapeutic target for anticancer agents against a variety of cancer types. In the present study, andrographolide and its structurally modified analogues were investigated for their inhibitory activities on hTopo II α enzyme. Five out of nine andrographolide analogues potently reduced hTopo II α activity and inhibited cell proliferation in four mammalian cell lines (Hela, CHO, BCA-1 and HepG2 cells). IC 50 values for cytotoxicity of analogues 3A.1, 3A.2, 3A.3, 1B and 2C were 4 to 7 μM. Structure-activity relationship studies revealed that both core structure of andrographolide and silicon based molecule of functional group were important for the inhibition of hTopo II α activity whereas position C-19 of analogues was required for anti-proliferation. In addition, the analogue 2C at 10 μM concentration inhibited hTopo II α, and induced apoptosis with nuclear fragmentation and formation of apoptotic bodies in HepG2 cells. The analogue 2C may, therefore, have a therapeutic potential as effective anticancer agent targeting the hTopo II α functions. Keywords Andrographolide analogues. Apoptosis. Cancer. DNA topoisomerase II α inhibitor Recently, a number of semi-synthetic compounds derived from natural products have been demonstrated to greatly improve anticancer activities [5]. Modified natural compounds could, therefore, render greater potency and efficacy for the inhibition of cancer growth and proliferation [5-10]. For example, etoposide, a synthetically modified compound J. Nateewattana : P.
BMC Complementary and Alternative Medicine, 2012
Background Curcuma comosa Roxb. (C. comosa) is an indigenous medicinal herb that has been used in... more Background Curcuma comosa Roxb. (C. comosa) is an indigenous medicinal herb that has been used in Thailand as a dietary supplement to relieve postmenopausal symptoms. Recently, a novel phytoestrogen, (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol or compound 049, has been isolated and no study thus far has investigated the role of C. comosa in preventing metabolic alterations occurring in estrogen-deprived state. The present study investigated the long-term effects (12 weeks) of C. comosa hexane extract and compound 049 on insulin resistance in prolonged estrogen-deprived rats. Methods Female Sprague-Dawley rats were ovariectomized (OVX) and treated with C. comosa hexane extract (125 mg, 250 mg, or 500 mg/kg body weight (BW)) and compound 049 (50 mg/kg BW) intraperitoneally three times per week for 12 weeks. Body weight, food intake, visceral fat weight, uterine weight, serum lipid profile, glucose tolerance, insulin action on skeletal muscle glucose transport activity, and GLUT-4 pro...
Journal of Ethnopharmacology, 2016
Ethnopharmacological relevance Curcuma comosa Roxb. (C. comosa) or Wan Chak Motluk, Zingiberaceae... more Ethnopharmacological relevance Curcuma comosa Roxb. (C. comosa) or Wan Chak Motluk, Zingiberaceae family, has been used in Thai traditional medicine for the treatment of gynecological problems and inflammation.
Journal of Agricultural and Food Chemistry, 2017
Diarylheptanoids from Curcuma comosa, of the Zingiberaceae family, exhibit diverse estrogenic act... more Diarylheptanoids from Curcuma comosa, of the Zingiberaceae family, exhibit diverse estrogenic activities. In this study we investigated the estrogenic activity of a major hydroxyl diarylheptanoid, 7-(3,4-dihydroxyphenyl)-5-hydroxy-1-phenyl-(1E)-1-heptene (compound 092) isolated from C. comosa. The compound elicited different transcriptional activities of estrogen agonist at low concentrations (0.1−1 μM) and antagonist at high concentrations (10−50 μM) using luciferase reporter gene assay in HEK-293T cells. In human breast cancer (MCF-7) cells, compound 092 showed an anti-estrogenic activity by downregulating ERα-signaling and suppressing estrogen-responsive genes, whereas it attenuated the uterotrophic effect of estrogen in immature ovariectomized rats. Of note, compound 092 promoted mouse pre-osteoblastic (MC3T3-E1) cell differentiation and the related bone markers, indicating its positive osteogenic effect. Our findings highlight a new, nonsteroidal, estrogen agonist/ antagonist of catechol diarylheptanoid from C. comosa, which is scientific evidence supporting its potential as a dietary supplement to prevent bone loss with low risk of breast and uterine cancers in postmenopausal women.
Biomedicine & Pharmacotherapy
Biomedicine & Pharmacotherapy
Bioorganic & Medicinal Chemistry Letters
RSC Advances
A novel and concise synthetic approach for the preparation of 6,20-epoxy ent-kaurane diterpenoid ... more A novel and concise synthetic approach for the preparation of 6,20-epoxy ent-kaurane diterpenoid from oridonin was established.
Chinese Journal of Organic Chemistry
A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was i... more A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was isolated from a marine sediment (-68 m) collected in South China Sea by means of intergrated chemical and bioactive screening method. Eleven compounds including mycophenolic acid (3) and its seven analogues (1, 2 and 4～8) were isolated from a nutrient-poor fermentation broth of P. brevicompactum OUCMDZ-4920, among which (±)-brevicolides A (1) and B (2) were new compounds. On the bases of spectroscopic and electronic circular dichroism (ECD) analyses, chemical transformation, chiral separation and Mosher's method, new compounds (-)-brevicolide A (1a), (＋)-brevicolide A (1b), (-)-brevicolide B (2a) and (＋)-brevicolide B (2b) were identified as 7-hydroxy-6-((S)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydrofuran-2yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((R)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((S)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran
![Research paper thumbnail of {"__content__"=>"Polyketides From the Endophytic Fungus sp. Isolated From the Mangrove Plant .", "i"=>[{"__content__"=>"Cladosporium"}, {"__content__"=>"Excoecaria agallocha"}]}](https://attachments.academia-assets.com/73466433/thumbnails/1.jpg)
](Frontiers in chemistry, 2018
Five new polyketides (-) and ten known compounds ( and -) were obtained from the fermentation pro... more Five new polyketides (-) and ten known compounds ( and -) were obtained from the fermentation products of the endophytic fungus sp. OUCMDZ-302 with the mangrove plant, (Euphorbiaceae). The new structures of - were established on the basis of ECD, specific rotation and spectroscopic data as well as the chemical calculation. Compound showed cytotoxicity against H1975 cell line with an IC value of 10.0 μM. Compounds and - showed radical scavenging activity against DPPH with the IC values of 2.65, 0.24, 5.66, and 6.67 μM, respectively. In addition, the absolute configuration of compound was solidly determined by X-ray and sugar analysis of the acidic hydrolysates for the first time as well as those of compounds - in this paper.
Phytochemistry, 2020
The chemical study on the heartwoods extract of Ventilago harmandiana (Rhamnaceae) resulted in th... more The chemical study on the heartwoods extract of Ventilago harmandiana (Rhamnaceae) resulted in the isolation of ten previously undescribed pyranonaphthoquinones (ventilanones A−J), an undescribed anthraquinone (ventilanone K), together with eight known anthraquinone derivatives. Their structures were elucidated by extensive analysis of their spectroscopic data. The absolute configuration of ventilanone A was established from single crystal X-ray crystallographic analysis of its p-bromobenzenesulfonate ester derivative using Cu Kα radiation. The absolute configurations of the other related compounds were identified by comparison of their ECD data with those of ventilanone A and related known compounds. Cytotoxic and anti-inflammatory activities of some of the isolated compounds were evaluated. Ventilanone A and ventilanone C exhibited moderate cytotoxicity against P-388 cell line. Ventilanone D exhibited significant anti-inflammatory activity while ventilanone A and ventilanone C showed moderate activity.
Scientific Reports, 2018
The Wnt/β-catenin signaling pathway plays a key role in the progression of human colorectal cance... more The Wnt/β-catenin signaling pathway plays a key role in the progression of human colorectal cancers (CRCs) and is one of the leading targets of chemotherapy agents developed for CRC. The present study aimed to investigate the anti-cancer effects and molecular mechanisms of 19-O-triphenylmethyl andrographolide (RS-PP-050), an andrographolide analogue and determine its activity in the Wnt/β-catenin pathway. RS-PP-050 was found to potently inhibit the proliferation and survival of HT-29 CRC cells. It induces cell cycle arrest and promotes apoptotic cell death which was associated with the activation of PARP-1 and p53. Furthermore, RS-PP-050 exerts inhibitory effects on β-catenin transcription by suppressing T-cell factor/lymphocyte enhancer factor (TCF/LEF) activity in cells overexpressing β-catenin and by down-regulating the endogenous expression of Wnt target genes. RS-PP-050 also decreased the protein expression of the active form of β-catenin but functions independently of GSK-3β, ...
Introduction. Currently, a number of semi-synthetic of natural plant compounds have been develope... more Introduction. Currently, a number of semi-synthetic of natural plant compounds have been developed to improve its effectiveness for treatment of cancers. In the present study, we investigated the anti-proliferative activity and apoptosis induction of MUC-30 in human breast cancer cells (MCF-7). MUC-30, a semi- synthetic analog of lignan, isolated from Phyllanthus taxodiifolius Beille (Krai Hang Nak). Methods. MCF-7 cells were treated with various concentrations of MUC-30 (0.01-10 µM) for 24-72 h and cell viability was evaluated by MTT assay. The anti-proliferative effect of the compound to MCF-7 cells via apoptosis pathway was determined by using DAPI assay, flow cytometry analysis, and the protein expression of PARP-1. Results. MUC-30 potently inhibited the proliferation of MCF-7 cells in a concentration- and time-related manners. Its IC50 (concentration that inhibits 50% of cell growth) was approximately 0.23 ± 0.07 µM at 72 h. The compound induced morphological changes of nucleus...
Phytochemistry Letters, 2020
Natural Product Communications, 2014
Bioassay-guided fractionation of the cytotoxic ethyl acetate fraction of the sequential methanol ... more Bioassay-guided fractionation of the cytotoxic ethyl acetate fraction of the sequential methanol extract from the leaves and twigs of Dasymaschalon sootepense led to the isolation of a new 7-hydroxy aporphine alkaloid, 6a,7-dehydrodasymachaline (1) along with the five known compounds (-)-nordicentrine (2), dicentrinone (3), (-)-sinactine (4), aristolactam AII (5) and epiberberine (6). Their structures were elucidated by spectroscopic methods. This is the first report of alkaloids 1–2 and 5–6 from the genus Dasymaschalon. Compounds 1 and 5 showed cytotoxicity against a panel of cancer cell lines.
Biomedicine & Pharmacotherapy, 2018
Hyperactivation of Wnt/β-catenin signaling implicated in oncogenesis of colorectal cancer (CRC) i... more Hyperactivation of Wnt/β-catenin signaling implicated in oncogenesis of colorectal cancer (CRC) is a potential molecular target for chemotherapy. An andrographolide analogue, 3A.1 (19-tert-butyldiphenylsilyl-8, 17-epoxy andrographolide) has previously been reported to be potently cytotoxic toward cancer cells by unknown molecular mechanisms. The present study explored the anti-cancer activity of analogue 3A.1 on Wnt/β-catenin signaling in colon cancer cells (HT29 cells) which were more sensitive to the others (HCT116 and SW480 cells). Analogue 3A.1 inhibited viability of HT29 cells with IC 50 value of 11.1 ± 1.4 μM at 24 h, which was more potent than that of the parent andrographolide. Analogue 3A.1 also suppressed the proliferation of HT29 cells and induced cell apoptosis in a dose-dependent manner. Its apoptotic activity was accompanied with increased expressions of proteins related to DNA damages; PARP-1 and γ-H2AX. In addition, analogue 3A.1 significantly inhibited T-cell factor and lymphoid enhancer factor (TCF/LEF) promoter activity of Wnt/β-catenin signaling. Accordingly, the expressions of Wnt target genes and β-catenin protein were suppressed. Moreover, analogue 3A.1 increased the activity of GSK-3β kinase, which is a negative regulator responsible for degradation of intracellular β-catenin. This mode of action was further supported by the absence of the effects after treatment with a GSK-3β inhibitor, and over-expression of a mutant β-catenin (S33Y). Our findings reveal, for the first time, an insight into the molecular mechanism of the anti-cancer activity of analogue 3A.1 through the inhibition of Wnt/β-catenin/GSK-3β pathway and provide a therapeutic potential of the andrographolide analogue 3A.1 in CRC treatment.
Organic Chemistry Frontiers, 2018
Secopaxilline A, featuring a C–N cleavage of an indole-diterpenoid skeleton, was isolated from Pe... more Secopaxilline A, featuring a C–N cleavage of an indole-diterpenoid skeleton, was isolated from Penicillium camemberti and synthesized from paxilline.
Investigational New Drugs, 2012
Topoisomerase II α enzyme plays a critical role in DNA replication process. It controls the topol... more Topoisomerase II α enzyme plays a critical role in DNA replication process. It controls the topologic states of DNA during transcription and is essential for cell proliferation. Human DNA topoisomerase II α (hTopo II α) is a promising chemotherapeutic target for anticancer agents against a variety of cancer types. In the present study, andrographolide and its structurally modified analogues were investigated for their inhibitory activities on hTopo II α enzyme. Five out of nine andrographolide analogues potently reduced hTopo II α activity and inhibited cell proliferation in four mammalian cell lines (Hela, CHO, BCA-1 and HepG2 cells). IC 50 values for cytotoxicity of analogues 3A.1, 3A.2, 3A.3, 1B and 2C were 4 to 7 μM. Structure-activity relationship studies revealed that both core structure of andrographolide and silicon based molecule of functional group were important for the inhibition of hTopo II α activity whereas position C-19 of analogues was required for anti-proliferation. In addition, the analogue 2C at 10 μM concentration inhibited hTopo II α, and induced apoptosis with nuclear fragmentation and formation of apoptotic bodies in HepG2 cells. The analogue 2C may, therefore, have a therapeutic potential as effective anticancer agent targeting the hTopo II α functions. Keywords Andrographolide analogues. Apoptosis. Cancer. DNA topoisomerase II α inhibitor Recently, a number of semi-synthetic compounds derived from natural products have been demonstrated to greatly improve anticancer activities [5]. Modified natural compounds could, therefore, render greater potency and efficacy for the inhibition of cancer growth and proliferation [5-10]. For example, etoposide, a synthetically modified compound J. Nateewattana : P.
BMC Complementary and Alternative Medicine, 2012
Background Curcuma comosa Roxb. (C. comosa) is an indigenous medicinal herb that has been used in... more Background Curcuma comosa Roxb. (C. comosa) is an indigenous medicinal herb that has been used in Thailand as a dietary supplement to relieve postmenopausal symptoms. Recently, a novel phytoestrogen, (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol or compound 049, has been isolated and no study thus far has investigated the role of C. comosa in preventing metabolic alterations occurring in estrogen-deprived state. The present study investigated the long-term effects (12 weeks) of C. comosa hexane extract and compound 049 on insulin resistance in prolonged estrogen-deprived rats. Methods Female Sprague-Dawley rats were ovariectomized (OVX) and treated with C. comosa hexane extract (125 mg, 250 mg, or 500 mg/kg body weight (BW)) and compound 049 (50 mg/kg BW) intraperitoneally three times per week for 12 weeks. Body weight, food intake, visceral fat weight, uterine weight, serum lipid profile, glucose tolerance, insulin action on skeletal muscle glucose transport activity, and GLUT-4 pro...
Journal of Ethnopharmacology, 2016
Ethnopharmacological relevance Curcuma comosa Roxb. (C. comosa) or Wan Chak Motluk, Zingiberaceae... more Ethnopharmacological relevance Curcuma comosa Roxb. (C. comosa) or Wan Chak Motluk, Zingiberaceae family, has been used in Thai traditional medicine for the treatment of gynecological problems and inflammation.
Journal of Agricultural and Food Chemistry, 2017
Diarylheptanoids from Curcuma comosa, of the Zingiberaceae family, exhibit diverse estrogenic act... more Diarylheptanoids from Curcuma comosa, of the Zingiberaceae family, exhibit diverse estrogenic activities. In this study we investigated the estrogenic activity of a major hydroxyl diarylheptanoid, 7-(3,4-dihydroxyphenyl)-5-hydroxy-1-phenyl-(1E)-1-heptene (compound 092) isolated from C. comosa. The compound elicited different transcriptional activities of estrogen agonist at low concentrations (0.1−1 μM) and antagonist at high concentrations (10−50 μM) using luciferase reporter gene assay in HEK-293T cells. In human breast cancer (MCF-7) cells, compound 092 showed an anti-estrogenic activity by downregulating ERα-signaling and suppressing estrogen-responsive genes, whereas it attenuated the uterotrophic effect of estrogen in immature ovariectomized rats. Of note, compound 092 promoted mouse pre-osteoblastic (MC3T3-E1) cell differentiation and the related bone markers, indicating its positive osteogenic effect. Our findings highlight a new, nonsteroidal, estrogen agonist/ antagonist of catechol diarylheptanoid from C. comosa, which is scientific evidence supporting its potential as a dietary supplement to prevent bone loss with low risk of breast and uterine cancers in postmenopausal women.
Biomedicine & Pharmacotherapy
Biomedicine & Pharmacotherapy
Bioorganic & Medicinal Chemistry Letters
RSC Advances
A novel and concise synthetic approach for the preparation of 6,20-epoxy ent-kaurane diterpenoid ... more A novel and concise synthetic approach for the preparation of 6,20-epoxy ent-kaurane diterpenoid from oridonin was established.
Chinese Journal of Organic Chemistry
A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was i... more A mycophenolic acid producing strain OUCMDZ-4920, identified as Penicillium brevicompactum, was isolated from a marine sediment (-68 m) collected in South China Sea by means of intergrated chemical and bioactive screening method. Eleven compounds including mycophenolic acid (3) and its seven analogues (1, 2 and 4～8) were isolated from a nutrient-poor fermentation broth of P. brevicompactum OUCMDZ-4920, among which (±)-brevicolides A (1) and B (2) were new compounds. On the bases of spectroscopic and electronic circular dichroism (ECD) analyses, chemical transformation, chiral separation and Mosher's method, new compounds (-)-brevicolide A (1a), (＋)-brevicolide A (1b), (-)-brevicolide B (2a) and (＋)-brevicolide B (2b) were identified as 7-hydroxy-6-((S)-2-hydroxy-2-((R)-2-methyl-5-oxotetrahydrofuran-2yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((R)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran-2yl)ethyl)-5-methoxy-4-methylisobenzofuran-1(3H)-one, 7-hydroxy-6-((S)-2-hydroxy-2-((S)-2-methyl-5-oxotetrahydrofuran
Frontiers in chemistry, 2018
Five new polyketides (-) and ten known compounds ( and -) were obtained from the fermentation pro... more Five new polyketides (-) and ten known compounds ( and -) were obtained from the fermentation products of the endophytic fungus sp. OUCMDZ-302 with the mangrove plant, (Euphorbiaceae). The new structures of - were established on the basis of ECD, specific rotation and spectroscopic data as well as the chemical calculation. Compound showed cytotoxicity against H1975 cell line with an IC value of 10.0 μM. Compounds and - showed radical scavenging activity against DPPH with the IC values of 2.65, 0.24, 5.66, and 6.67 μM, respectively. In addition, the absolute configuration of compound was solidly determined by X-ray and sugar analysis of the acidic hydrolysates for the first time as well as those of compounds - in this paper.