Four neo-lignans: isoamericanin A(1), isoamericanol A(2), americanin B(3), artabotrycinol(4), a hemiterpenoid: (R)-artabotriol(5) and other compounds: palmitic acid(6), β-sitosterol(7) and daucosterol(8) were isolate...Four neo-lignans: isoamericanin A(1), isoamericanol A(2), americanin B(3), artabotrycinol(4), a hemiterpenoid: (R)-artabotriol(5) and other compounds: palmitic acid(6), β-sitosterol(7) and daucosterol(8) were isolated from the seeds of Artabostrys hexapetalus (L.f.) Bhadari (Annonaceae). Artabotrycinol(4) is a new neo-lignan and (R)-artabotriol(5) is a new hemiterpenoid. Their structures were established by IR, UV, MS, 1D and 2D NMR. Three other neo-lignans 1, 2, 3 were isolated from this plant for the first time.展开更多
Objective:To evaluate the potential efficacy of seed extracts of Annona squamosa and Annona muricata used as natural insecticides to control adult and larvae of the vectors Aedes albopictus and Culex quinquefasciatus ...Objective:To evaluate the potential efficacy of seed extracts of Annona squamosa and Annona muricata used as natural insecticides to control adult and larvae of the vectors Aedes albopictus and Culex quinquefasciatus under laboratory conditions.Methods:Aqueous and oil extracts of the two plants were prepared from dried seeds.Preliminary identifications of the chemical components of each seed extracts were performed using microreactional and GCP techniques.Larvae and adults of Aedes albopictus and Culex quinquefasciatus were collected from the breeding sites in coastal and highlands regions of Madagascar.WHO standardized tests of susceptibility for larvae and imaginal stage of mosquitoes were realized to determine mortality and LC_(50) of mosquitoes.Results:Chemical identifications showed that these extracts contain alkaloids and flavonoids compounds that probably confer their biological insecticidal proprieties.CPG analysis showed also the presence of various fatty acids.On adult mosquitoes,significant insecticidal effects were observed with both aqueous and oil extracts of the two plant seeds compared to mortality induced by deltamethrin,an insecticide used as reference.Extracts of Annona muricata induced high mortality rate to both species of mosquito compared to extracts of Annona squamosa at all concentrations tested.The LC_(50) of seed extracts ranged from 1%to 5%for adults and 0.5%to 1%for larvae.Conclusions:The seed extracts of these two plants may be used as mosquito controlling agents and offer a new approach to a less costly,practical and environmentally friendly control of vector borne diseases.展开更多
Two new species of Polyalthiopsis(Annonaceae),P.nigra Y.H.Tan & Bin Yang from Guangxi and Yunnan Provinces and P.xui Y.H.Tan & Bin Yang from Yunnan Province,are described and illustrated.P.nigra is morphologic...Two new species of Polyalthiopsis(Annonaceae),P.nigra Y.H.Tan & Bin Yang from Guangxi and Yunnan Provinces and P.xui Y.H.Tan & Bin Yang from Yunnan Province,are described and illustrated.P.nigra is morphologically similar to P.chinensis in having narrowly elliptic-oblong,lemon to yellowish green petals,but differs by having obovoid monocarps,a higher number of leaf secondary veins,leaf blades usually widest above the middle,and a lower ratio of leaf blade length to width.P.xui is morphologically similar to P.floribunda in having axillary inflorescences,1-3(-4) flowers,elliptic leaves,and ellipticovate petals,but differs in the numbers of carpels per flower and ovules per carpel.The molecular phylogenetic analysis using five plastid markers confirm that the two new species belong to the genus Polyalthiopsis and show clear interspecific divergences between P.nigra and P.xui and between them and other species in the genus.Detailed descriptions,colored photographs,and habitat and distribution data for the two new species are provided.In addition,the fruit morphology of P.chinensis is described for the first time,based on living collections.Geographical distributions and a diagnostic key for all Polyalthiopsis species are also presented.展开更多
Squamostatin-B (1), a new polyketide or acetogenin, has been isolated from Annona squamosa L. (Annonaceae). Its structure and relative atereochemistry were elucidated on the basis of the spectral analyses of 1 and its...Squamostatin-B (1), a new polyketide or acetogenin, has been isolated from Annona squamosa L. (Annonaceae). Its structure and relative atereochemistry were elucidated on the basis of the spectral analyses of 1 and its derivatives, the acetate (2) and mesitoate (3).展开更多
Muricatenol 1, a new acetogenin, has been isolated from the seeds of Annona muricata L.. Compound 1 is a C-37 acetogenin without any THF rings. with four hydroxyls and one double bond in the long aliphatic chain. The ...Muricatenol 1, a new acetogenin, has been isolated from the seeds of Annona muricata L.. Compound 1 is a C-37 acetogenin without any THF rings. with four hydroxyls and one double bond in the long aliphatic chain. The hydroxyls of 1 are located at C-4, C-10, C-18 and C-19. respectively. The vicinal diet at C-18/C-19 is threo-configuration, and the double bond at C-14/C-15 is cis-configuration.展开更多
Uvaria tortilis is a lianescent annonaceous species endemic to the Côte d’Ivoire where it is used to treat amenorrhea and as uterotonic. Thus, the MeOH crude extract of its stem barks was investigated in orde...Uvaria tortilis is a lianescent annonaceous species endemic to the Côte d’Ivoire where it is used to treat amenorrhea and as uterotonic. Thus, the MeOH crude extract of its stem barks was investigated in order to determine the chemical composition. A new C-benzyl hydroxlated, uvriatortilisin (1), together with six known compounds, dichamanetin (2), β-sitosterol (3), stigmasterol (4), chamanetin (5), uvaretin (6) and (-)-epicatechin (7), were isolated. Structure of these compounds was elucidated using spectroscopic techniques, including IR, UV, MS and NMR (1D and 2D). Certain compounds could be considered to have chemotaxonomic value.展开更多
Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other...Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other related genera by its conspicuous ring of staminodes formed by the enlarged outer stamens, which is unique in the Annonaceae, and by an entirely fused calyx, combined with the fully syncarpous fruits with a basal collar. The general wood anatomical characters are in line with the very specific wood anatomy of the family, characterized by the tangential, concentric parenchyma bands. There is, however, one very specific feature in Fusaea : the small rhombic crystals in the ray cells. From the combined evidence from flower, fruit and pollen morphology, we can conclude that Fusaea is closely related to Duckeanthus, Duguetia, Pachypodanthium, Letestudoxa and probably Pseudartabotrys . Based on measurements of the diagnostic features on all the 158 available specimens identified either as F.longifolia or F.decurrens , we constructed three scatter diagrams to show the continuous variation of the distinguishing characters previously used. F.decurrens is obviously within the morphological variation range of F.longifolia , and is therefore brought into synonymy with the latter. Two species, i.e., F.longifolia and F.peruviana , are recognized in this genus.展开更多
Although ＂dry-type＂ stigmas are widely re- garded as ancestral in angiosperms, the early-divergent family Annonaceae has copious stigmatic exudate. We evaluate three putative functions for this exudate： as a nutrit...Although ＂dry-type＂ stigmas are widely re- garded as ancestral in angiosperms, the early-divergent family Annonaceae has copious stigmatic exudate. We evaluate three putative functions for this exudate： as a nutritive reward for pollinators; as a pollen germination medium; and as an extragynoecial compitum that enables pollen tube growth between carpels. Stigmatic exudate is fructose dominated （72.2%）, but with high levels of glucose and sucrose; the dominance of hexose sugars and the diversity of amino acids observed, including many that are essential for insects, support a nutritive role for pollinators. Sugar concentration in pre-receptive flowers is high （28.2%）, falling during the peak period of stigmatic receptivity （17.4%）, and then rising again toward the end of the pistillate phase （32.9%）. Pollen germination was highest in sugar concentrations 〈2%. Sugar concentrations during the peak pistillate phase therefore provide optimal osmolarity for pollen hydration and germination; subsequent changes in sugar concentration during anthesis reinforce protogyny （in which carpels mature before stamens）, enabling the retention of concentrated exudate into the staminate phase as a pollinator food reward without the possibility of pollen germination. Intercarpellary growth of pollen tubes was confirmed： the exudate therefore also functions as a suprastylar extragynoecial compitum, overcoming the limitations of apocarpy.展开更多
The seedling phase represents an initial and critical stage for the establishment of individuals in the ecosystem.During this stage,specialized metabolites contribute to survival;however,studies analyzing the presence...The seedling phase represents an initial and critical stage for the establishment of individuals in the ecosystem.During this stage,specialized metabolites contribute to survival;however,studies analyzing the presence of these molecules and the reasons for their production and accumulation are still scarce.Annonaceae is a botanical family recognized for the chemodiversity of its secondary metabolites;nearly 1000 alkaloids have been reported in approximately 150 adult specimens.The aim of this studywas to determinewhether alkaloid biosynthesis in Annonaceae is expressed from early stages.For this purpose,Annona macroprophyllata,Annona muricata,Annona purpurea,and Annona reticulata seedlings,tropical Annonaceae with a history of alkaloids in adult stages,were studied.Alkaloidswere extracted using the selective acid-basemethod fromroots,stems,and leaves of seedlings with one to two pairs of leaves.The chemical composition analysis was performed using gas chromatography coupled to a mass spectrum.The identity of molecules was confirmed with standards and bibliographical references.Alkaloids were detected in the tissues of all species,and 28 of these metabolites were identified,92%with a benzylisoquinoline structure.Many of them have reports of various biological activities.These alkaloids are not derived fromthe mother plant,as no alkaloidswere found in the seeds.Nine,nine,eight,and twenty alkaloids were detected in seedlings of A.macroprophyllata,A.muricata,A.reticulata,and A.purpurea,respectively.The roots of all species are the organs with the most alkaloids(both in abundance and chemical richness).In conclusion,alkaloid metabolism is expressed during the early development stages in Annonaceae and could be associated with the chemical defense theory.These findings enhance our understanding of how seedlings use chemical strategies to adapt to their environment.They also demonstrate that seedlings can produce active compounds,even when grown under controlled conditions.展开更多
A new special flavone, named desmosdumotin B, was isolated from the roots of D. dumosus and its chemical structure identified as 5-hydroxy-7-one-6,8,8-trimethylflavone by spectral analysis and X-ray.
Two new cyclopeptides, leiocyclocin A (1); B (2), were isolated from the seeds of Goniothalanus leiocarpus. Their structures were elucidated by means of spectral and chemical methods.
Calamistrin E, the first Annonaceous acetogenin with C=C bond in the aliphatic chain from the genus Uvaria was isolated from U. calamistrata. Its structure including relative and absolute configurations was determined...Calamistrin E, the first Annonaceous acetogenin with C=C bond in the aliphatic chain from the genus Uvaria was isolated from U. calamistrata. Its structure including relative and absolute configurations was determined by chemical derivation and spectral analysis.展开更多
Two new polyoxygenated cyclohexenes, kweichowenol A and B were isolated from the leaves of Uvaria kweichowensis and their structures were established on the basis of their spectral data.
Two mild-cytotoxic bistetrahydrofuran (THF) ring annonaceous acetogenins named calamistrins F(1) and G(2) were isolated from the ethanolic extract of the roots of U. calamistrata Hance. Their structures including the ...Two mild-cytotoxic bistetrahydrofuran (THF) ring annonaceous acetogenins named calamistrins F(1) and G(2) were isolated from the ethanolic extract of the roots of U. calamistrata Hance. Their structures including the relative and absolute configurations were determined by chemical derivation and spectral analysis. Calamistrins F and G were a pair of epimers at C-26 which both had THF ring from C-18 to C-25 and three OH groups at C-5, C-17 and C-26.展开更多
Three new styrylpyrones. named 7-epi-goniodiol 1. leiocarpin B 2 and leiocarpin C 3.were isolated from the stem barks of Goniothalamus leiocarpus. Their structures were elucidated bymeans of spectral and chemical meth...Three new styrylpyrones. named 7-epi-goniodiol 1. leiocarpin B 2 and leiocarpin C 3.were isolated from the stem barks of Goniothalamus leiocarpus. Their structures were elucidated bymeans of spectral and chemical methods. The relative configuration of 1 and 2 were determined byX-ray crystallographic analysis.展开更多
Two new polyoxygenated cyclohexenes,named uvacalolA(1),and B(2)were isolated from the rhizomes of Uvaria calamistrata.On the basis of spectral analysis and chemical derivatization,including preparation of Mosher ester...Two new polyoxygenated cyclohexenes,named uvacalolA(1),and B(2)were isolated from the rhizomes of Uvaria calamistrata.On the basis of spectral analysis and chemical derivatization,including preparation of Mosher esters,the structure of 1 to 2 were established.展开更多
A new benzosesquiterpenoid dimer, 3 ' ,3 ' ' ' -bispolycerasoidol (1), along with its monomer, polycerasoidol, were isolated from the dried leaves of Polyalthia cheliensis Hu. The structure of 1 was es...A new benzosesquiterpenoid dimer, 3 ' ,3 ' ' ' -bispolycerasoidol (1), along with its monomer, polycerasoidol, were isolated from the dried leaves of Polyalthia cheliensis Hu. The structure of 1 was established by spectroscopic methods.展开更多
Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog(MS)medium supplemented with different concentrations of 1-naphthylacetic acid(NAA),6-benzyladenine(BA)and 2,4-dichlorophenoxya...Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog(MS)medium supplemented with different concentrations of 1-naphthylacetic acid(NAA),6-benzyladenine(BA)and 2,4-dichlorophenoxyacetic acid(2,4-D)utilized hypocotyls with explant.The highest percentage of callus formation was the treatment supplemented with 3 mg L-1 NAA for A.muricata(100%)while for A.purpurea in lower percentage(75%).BA stimulated the formation of shoots in all the evaluated concentrations,being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for A.muricata(23 shoots/explant)and A.purpurea(28 shoots/explant).The content of total phenols,flavonoids and antioxidant activity was measured in the callus obtained from both species.The results showed that a higher content of total phenols was quantified in callus of A.purpurea(27.8 mg g-1 dw)compared to A.muricata(23.2 mg g-1 dw).The highest content of total flavonoids was observed in the callus of A.purpurea(8.0μg g-1 dw).Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical assay.The concentration required for 50%inhibition(IC50)of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22μg mL-1 in methanolic extracts of callus of A.muricata,while in extracts of callus of A.purpurea was 2.86μg mL-1,in both cases was greater than that found for leaves.Callus culture of the species studied in this work represents an alternative for the production of natural antioxidants.展开更多
文摘Four neo-lignans: isoamericanin A(1), isoamericanol A(2), americanin B(3), artabotrycinol(4), a hemiterpenoid: (R)-artabotriol(5) and other compounds: palmitic acid(6), β-sitosterol(7) and daucosterol(8) were isolated from the seeds of Artabostrys hexapetalus (L.f.) Bhadari (Annonaceae). Artabotrycinol(4) is a new neo-lignan and (R)-artabotriol(5) is a new hemiterpenoid. Their structures were established by IR, UV, MS, 1D and 2D NMR. Three other neo-lignans 1, 2, 3 were isolated from this plant for the first time.
基金Supported by the grants FRB-CD-AOOI-07-012 and CMIRA Coopera 2011 from Region Rhne-Alpes 11MIF-MAVINGUI-10851
文摘Objective:To evaluate the potential efficacy of seed extracts of Annona squamosa and Annona muricata used as natural insecticides to control adult and larvae of the vectors Aedes albopictus and Culex quinquefasciatus under laboratory conditions.Methods:Aqueous and oil extracts of the two plants were prepared from dried seeds.Preliminary identifications of the chemical components of each seed extracts were performed using microreactional and GCP techniques.Larvae and adults of Aedes albopictus and Culex quinquefasciatus were collected from the breeding sites in coastal and highlands regions of Madagascar.WHO standardized tests of susceptibility for larvae and imaginal stage of mosquitoes were realized to determine mortality and LC_(50) of mosquitoes.Results:Chemical identifications showed that these extracts contain alkaloids and flavonoids compounds that probably confer their biological insecticidal proprieties.CPG analysis showed also the presence of various fatty acids.On adult mosquitoes,significant insecticidal effects were observed with both aqueous and oil extracts of the two plant seeds compared to mortality induced by deltamethrin,an insecticide used as reference.Extracts of Annona muricata induced high mortality rate to both species of mosquito compared to extracts of Annona squamosa at all concentrations tested.The LC_(50) of seed extracts ranged from 1%to 5%for adults and 0.5%to 1%for larvae.Conclusions:The seed extracts of these two plants may be used as mosquito controlling agents and offer a new approach to a less costly,practical and environmentally friendly control of vector borne diseases.
基金funded by the National Natural Science Foundation of China (Grants Nos.31900180 and 31970223)the Special Fund of Yunnan Fundamental Research Projects (Grant No.202101AT070058)+3 种基金the project of the Yunnan Academy of Forestry and Grassland (Grant No.KFJJ21-01)the Project of National Plant Specimen Resource Center (NPSRC) (E0117G1001)the Biodiversity Investigation Observation and Assessment Program (2019-2023) of Ministry of Ecology and Environment of Chinathe project of the Southeast Asia Biodiversity Research Institute,Chinese Academy of Sciences (Grant No.Y4ZK111B01)。
文摘Two new species of Polyalthiopsis(Annonaceae),P.nigra Y.H.Tan & Bin Yang from Guangxi and Yunnan Provinces and P.xui Y.H.Tan & Bin Yang from Yunnan Province,are described and illustrated.P.nigra is morphologically similar to P.chinensis in having narrowly elliptic-oblong,lemon to yellowish green petals,but differs by having obovoid monocarps,a higher number of leaf secondary veins,leaf blades usually widest above the middle,and a lower ratio of leaf blade length to width.P.xui is morphologically similar to P.floribunda in having axillary inflorescences,1-3(-4) flowers,elliptic leaves,and ellipticovate petals,but differs in the numbers of carpels per flower and ovules per carpel.The molecular phylogenetic analysis using five plastid markers confirm that the two new species belong to the genus Polyalthiopsis and show clear interspecific divergences between P.nigra and P.xui and between them and other species in the genus.Detailed descriptions,colored photographs,and habitat and distribution data for the two new species are provided.In addition,the fruit morphology of P.chinensis is described for the first time,based on living collections.Geographical distributions and a diagnostic key for all Polyalthiopsis species are also presented.
基金Project supported by National Natural Science Foundation of China.
文摘Squamostatin-B (1), a new polyketide or acetogenin, has been isolated from Annona squamosa L. (Annonaceae). Its structure and relative atereochemistry were elucidated on the basis of the spectral analyses of 1 and its derivatives, the acetate (2) and mesitoate (3).
文摘Muricatenol 1, a new acetogenin, has been isolated from the seeds of Annona muricata L.. Compound 1 is a C-37 acetogenin without any THF rings. with four hydroxyls and one double bond in the long aliphatic chain. The hydroxyls of 1 are located at C-4, C-10, C-18 and C-19. respectively. The vicinal diet at C-18/C-19 is threo-configuration, and the double bond at C-14/C-15 is cis-configuration.
文摘Uvaria tortilis is a lianescent annonaceous species endemic to the Côte d’Ivoire where it is used to treat amenorrhea and as uterotonic. Thus, the MeOH crude extract of its stem barks was investigated in order to determine the chemical composition. A new C-benzyl hydroxlated, uvriatortilisin (1), together with six known compounds, dichamanetin (2), β-sitosterol (3), stigmasterol (4), chamanetin (5), uvaretin (6) and (-)-epicatechin (7), were isolated. Structure of these compounds was elucidated using spectroscopic techniques, including IR, UV, MS and NMR (1D and 2D). Certain compounds could be considered to have chemotaxonomic value.
文摘Fusaea occurs in Colombia, Venezuela, the three Guianas, Ecuador, Peru, Brazi land Bolivia. It is found in non inundated and inundated rain forest at elevations from sea level to 600(-900)m. It is distinct from other related genera by its conspicuous ring of staminodes formed by the enlarged outer stamens, which is unique in the Annonaceae, and by an entirely fused calyx, combined with the fully syncarpous fruits with a basal collar. The general wood anatomical characters are in line with the very specific wood anatomy of the family, characterized by the tangential, concentric parenchyma bands. There is, however, one very specific feature in Fusaea : the small rhombic crystals in the ray cells. From the combined evidence from flower, fruit and pollen morphology, we can conclude that Fusaea is closely related to Duckeanthus, Duguetia, Pachypodanthium, Letestudoxa and probably Pseudartabotrys . Based on measurements of the diagnostic features on all the 158 available specimens identified either as F.longifolia or F.decurrens , we constructed three scatter diagrams to show the continuous variation of the distinguishing characters previously used. F.decurrens is obviously within the morphological variation range of F.longifolia , and is therefore brought into synonymy with the latter. Two species, i.e., F.longifolia and F.peruviana , are recognized in this genus.
基金funded by grants from the Hong Kong Research Grants Council(776713)the University of Hong Kong Research Committee,both awarded to R.M.K.S.and C.C.P.
文摘Although ＂dry-type＂ stigmas are widely re- garded as ancestral in angiosperms, the early-divergent family Annonaceae has copious stigmatic exudate. We evaluate three putative functions for this exudate： as a nutritive reward for pollinators; as a pollen germination medium; and as an extragynoecial compitum that enables pollen tube growth between carpels. Stigmatic exudate is fructose dominated （72.2%）, but with high levels of glucose and sucrose; the dominance of hexose sugars and the diversity of amino acids observed, including many that are essential for insects, support a nutritive role for pollinators. Sugar concentration in pre-receptive flowers is high （28.2%）, falling during the peak period of stigmatic receptivity （17.4%）, and then rising again toward the end of the pistillate phase （32.9%）. Pollen germination was highest in sugar concentrations 〈2%. Sugar concentrations during the peak pistillate phase therefore provide optimal osmolarity for pollen hydration and germination; subsequent changes in sugar concentration during anthesis reinforce protogyny （in which carpels mature before stamens）, enabling the retention of concentrated exudate into the staminate phase as a pollinator food reward without the possibility of pollen germination. Intercarpellary growth of pollen tubes was confirmed： the exudate therefore also functions as a suprastylar extragynoecial compitum, overcoming the limitations of apocarpy.
基金the call of“Ciencia de Frontera”(CF 2023-1-2756Consejo Nacional de Humanidades,Ciencias y Tecnologias).
文摘The seedling phase represents an initial and critical stage for the establishment of individuals in the ecosystem.During this stage,specialized metabolites contribute to survival;however,studies analyzing the presence of these molecules and the reasons for their production and accumulation are still scarce.Annonaceae is a botanical family recognized for the chemodiversity of its secondary metabolites;nearly 1000 alkaloids have been reported in approximately 150 adult specimens.The aim of this studywas to determinewhether alkaloid biosynthesis in Annonaceae is expressed from early stages.For this purpose,Annona macroprophyllata,Annona muricata,Annona purpurea,and Annona reticulata seedlings,tropical Annonaceae with a history of alkaloids in adult stages,were studied.Alkaloidswere extracted using the selective acid-basemethod fromroots,stems,and leaves of seedlings with one to two pairs of leaves.The chemical composition analysis was performed using gas chromatography coupled to a mass spectrum.The identity of molecules was confirmed with standards and bibliographical references.Alkaloids were detected in the tissues of all species,and 28 of these metabolites were identified,92%with a benzylisoquinoline structure.Many of them have reports of various biological activities.These alkaloids are not derived fromthe mother plant,as no alkaloidswere found in the seeds.Nine,nine,eight,and twenty alkaloids were detected in seedlings of A.macroprophyllata,A.muricata,A.reticulata,and A.purpurea,respectively.The roots of all species are the organs with the most alkaloids(both in abundance and chemical richness).In conclusion,alkaloid metabolism is expressed during the early development stages in Annonaceae and could be associated with the chemical defense theory.These findings enhance our understanding of how seedlings use chemical strategies to adapt to their environment.They also demonstrate that seedlings can produce active compounds,even when grown under controlled conditions.
文摘A new special flavone, named desmosdumotin B, was isolated from the roots of D. dumosus and its chemical structure identified as 5-hydroxy-7-one-6,8,8-trimethylflavone by spectral analysis and X-ray.
基金This work was supported by the National Natural Science Foundation of China(Grant No.39770089)the Applied and Basic Rcscarch Foundation of Yunnan province(Grant No.97B038q).
文摘Two new cyclopeptides, leiocyclocin A (1); B (2), were isolated from the seeds of Goniothalanus leiocarpus. Their structures were elucidated by means of spectral and chemical methods.
文摘Calamistrin E, the first Annonaceous acetogenin with C=C bond in the aliphatic chain from the genus Uvaria was isolated from U. calamistrata. Its structure including relative and absolute configurations was determined by chemical derivation and spectral analysis.
基金This project was supposed by the National Natural Sciences Foundation of China(No.30472077)the Natural Sciences Foundation of Beijing City(No.7052049).
文摘Two new polyoxygenated cyclohexenes, kweichowenol A and B were isolated from the leaves of Uvaria kweichowensis and their structures were established on the basis of their spectral data.
文摘Two mild-cytotoxic bistetrahydrofuran (THF) ring annonaceous acetogenins named calamistrins F(1) and G(2) were isolated from the ethanolic extract of the roots of U. calamistrata Hance. Their structures including the relative and absolute configurations were determined by chemical derivation and spectral analysis. Calamistrins F and G were a pair of epimers at C-26 which both had THF ring from C-18 to C-25 and three OH groups at C-5, C-17 and C-26.
文摘Three new styrylpyrones. named 7-epi-goniodiol 1. leiocarpin B 2 and leiocarpin C 3.were isolated from the stem barks of Goniothalamus leiocarpus. Their structures were elucidated bymeans of spectral and chemical methods. The relative configuration of 1 and 2 were determined byX-ray crystallographic analysis.
文摘Two new polyoxygenated cyclohexenes,named uvacalolA(1),and B(2)were isolated from the rhizomes of Uvaria calamistrata.On the basis of spectral analysis and chemical derivatization,including preparation of Mosher esters,the structure of 1 to 2 were established.
文摘A new benzosesquiterpenoid dimer, 3 ' ,3 ' ' ' -bispolycerasoidol (1), along with its monomer, polycerasoidol, were isolated from the dried leaves of Polyalthia cheliensis Hu. The structure of 1 was established by spectroscopic methods.
文摘Callus cultures of Annona muricata and Annona purpurea were induced in Murashige and Skoog(MS)medium supplemented with different concentrations of 1-naphthylacetic acid(NAA),6-benzyladenine(BA)and 2,4-dichlorophenoxyacetic acid(2,4-D)utilized hypocotyls with explant.The highest percentage of callus formation was the treatment supplemented with 3 mg L-1 NAA for A.muricata(100%)while for A.purpurea in lower percentage(75%).BA stimulated the formation of shoots in all the evaluated concentrations,being the concentration of 2 mg L-1 the one that induced the greater formation of shoots for A.muricata(23 shoots/explant)and A.purpurea(28 shoots/explant).The content of total phenols,flavonoids and antioxidant activity was measured in the callus obtained from both species.The results showed that a higher content of total phenols was quantified in callus of A.purpurea(27.8 mg g-1 dw)compared to A.muricata(23.2 mg g-1 dw).The highest content of total flavonoids was observed in the callus of A.purpurea(8.0μg g-1 dw).Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydracil radical assay.The concentration required for 50%inhibition(IC50)of the 2,2-diphenyl-1-picrylhydracil radicals were 4.22μg mL-1 in methanolic extracts of callus of A.muricata,while in extracts of callus of A.purpurea was 2.86μg mL-1,in both cases was greater than that found for leaves.Callus culture of the species studied in this work represents an alternative for the production of natural antioxidants.
