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Peter K Endress - One of the best experts on this subject based on the ideXlab platform.
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evidence on vegetative and inflorescence morphology of Chloranthaceae angiospermae from the early cretaceous middle late albian of spain
Journal of Systematic Palaeontology, 2020Co-Authors: Luis Miguel Sender, James A. Doyle, Peter K Endress, Garland R. Upchurch, Uxue Villanuevaamadoz, José B. DiezAbstract:The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative pa...
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Evidence on vegetative and inflorescence morphology of Chloranthaceae (Angiospermae) from the Early Cretaceous (middle–late Albian) of Spain
Journal of Systematic Palaeontology, 2020Co-Authors: Luis Miguel Sender, James A. Doyle, Peter K Endress, Garland R. Upchurch, Uxue Villanueva-amadoz, José B. DiezAbstract:The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative pa...
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Phylogenetic Analyses of Cretaceous Fossils Related to Chloranthaceae and their Evolutionary Implications
The Botanical Review, 2018Co-Authors: James A. Doyle, Peter K EndressAbstract:Chloranthaceae were one of the first common lines during the early radiation of angiosperms, possibly reflecting adaptation to more open habitats. Phylogenetic analyses clarify the position of Cretaceous mesofossils in molecular trees of Recent taxa. Plants that produced Asteropollis pollen, with tepals adnate to a single carpel, are nested in crown group Chloranthaceae with Hedyosmum ; Canrightiopsis , with three stamens and no perianth, is sister to Sarcandra and Chloranthus ; and Canrightia is a stem relative that illustrates a still bisexual stage in floral reduction. Plants that produced Pennipollis pollen are related to Chloranthaceae and/or Ceratophyllum rather than monocots. Appomattoxia , which produced Tucanopollis pollen, has equivocal affinities, but Pseudoasterophyllites , with similar pollen and stems with reduced leaves, may be a link between Chloranthaceae and Ceratophyllum . These results imply that flowers became unisexual before losing the perianth, while bisexual flowers in Canrightiopsis , Sarcandra , and Chloranthus are secondarily derived from unisexual flowers.
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reconstructing the ancestral angiosperm flower and its initial specializations
American Journal of Botany, 2009Co-Authors: Peter K Endress, James A. DoyleAbstract:: Increasingly robust understanding of angiosperm phylogeny allows more secure reconstruction of the flower in the most recent common ancestor of extant angiosperms and its early evolution. The surprising emergence of several extant and fossil taxa with simple flowers near the base of the angiosperms-Chloranthaceae, Ceratophyllum, Hydatellaceae, and the Early Cretaceous fossil Archaefructus (the last three are water plants)-has brought a new twist to this problem. We evaluate early floral evolution in angiosperms by parsimony optimization of morphological characters on phylogenetic trees derived from morphological and molecular data. Our analyses imply that Ceratophyllum may be related to Chloranthaceae, and Archaefructus to either Hydatellaceae or Ceratophyllum. Inferred ancestral features include more than two whorls (or series) of tepals and stamens, stamens with protruding adaxial or lateral pollen sacs, several free, ascidiate carpels closed by secretion, extended stigma, extragynoecial compitum, and one or several ventral pendent ovule(s). The ancestral state in other characters is equivocal: e.g., bisexual vs. unisexual flowers, whorled vs. spiral floral phyllotaxis, presence vs. absence of tepal differentiation, anatropous vs. orthotropous ovules. Our results indicate that the simple flowers of the newly recognized basal groups are reduced rather than primitively simple.
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Perianth Biology in the Basal Grade of Extant Angiosperms
International Journal of Plant Sciences, 2008Co-Authors: Peter K EndressAbstract:Perianth structure and behavior were studied comparatively in representatives of all families of the basalmost extant angiosperms (ANITA grade plus Chloranthaceae). In addition, data from the literature were reviewed. Tepal aestivation is spiral imbricate in Amborella and Austrobaileyales, with broadly overlapping flanks; aestivation is mainly contort within each of the two tepal whorls in Cabomba (but open within each whorl and imbricate only between whorls in Brasenia) and is whorled imbricate in Nymphaeaceae. Tepals are absent in Hydatellaceae, Chloranthaceae (other than Hedyosmum), and Ceratophyllaceae. In two genera of Nymphaeales (Cabomba and Nuphar), nectaries are present on inner tepals. Tepals are caducous during or at the end of anthesis in Austrobaileyales. Preformations of the tepal abscission zone in flowers with caducous tepals include a narrow tepal base, constriction as seen in median longitudinal sections, and small‐celled tissue. In contrast, the perianth organs of Amborella, Nymphaeales...
Xiao-shui Peng - One of the best experts on this subject based on the ideXlab platform.
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Total syntheses of shizukaols A and E.
Nature communications, 2018Co-Authors: Bencan Tang, Xiao-shui PengAbstract:Shizukaols possess a common heptacyclic framework containing more than ten contiguous stereocenters and potential biological activities. Here we report that the total syntheses of shizukaols A (1) and E (2), two lindenane-type dimers from the Chloranthaceae family, are achieved via a modified biomimetic Diels–Alder reaction. The common crucial biomimetic diene 23 and ethylene species (6, 17) are obtained through either a highly Z-selective olefination of α-siloxy ketone with ynolate anions or an intramolecular Horner–Wadsworth–Emmons olefination from commercially available Wieland–Miescher ketone (7). This synthetic approach here opens up practical avenues for the total syntheses of the intriguing Chloranthaceae family members, as well as the understanding of their relevant biological action in nature. Shizukaols, bioactive dimers naturally occurring in the Chloranthaceae family, possess a complex polycyclic framework with more than ten contiguous stereocenters. Here the authors report the total syntheses of shizukaols A and E achieved via a modified Diels–Alder reaction mimicking the biosynthetic pathway.
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Total syntheses of shizukaols A and E
Nature Publishing Group, 2018Co-Authors: Bencan Tang, Xiao-shui PengAbstract:Shizukaols, bioactive dimers naturally occurring in the Chloranthaceae family, possess a complex polycyclic framework with more than ten contiguous stereocenters. Here the authors report the total syntheses of shizukaols A and E achieved via a modified Diels–Alder reaction mimicking the biosynthetic pathway
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Synthetic studies toward lindenane-type dimers via Diels-Alder reaction
Tetrahedron, 2018Co-Authors: Henry N. C. Wong, Xiao-shui PengAbstract:Abstract Lindenane-type dimers are natural sesquiterpenoids, mainly from Chloranthaceae, possessing an unique heptacyclic skeleton and diverse bioactivities. Inspection of their structures suggested the possibility of deploying an endo Diels-Alder reaction to construct the key cyclohexene ring. In this article we investigated the feasibility of Diels-Alder reactions between various dienes and dienophiles, leading ultimately to their applications to the realization of [4 + 2] lindenane dimers.
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A concise construction of the chlorahololide heptacyclic core.
Organic letters, 2011Co-Authors: Xiao-shui PengAbstract:A concise and efficient strategy for the construction of the heptacyclic core of the Chloranthaceae family has been developed. The key strategy comprises an SN2-type intramolecular nucleophilic substitution and a biomimetic endo-Diels–Alder cycloaddition.
James A. Doyle - One of the best experts on this subject based on the ideXlab platform.
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evidence on vegetative and inflorescence morphology of Chloranthaceae angiospermae from the early cretaceous middle late albian of spain
Journal of Systematic Palaeontology, 2020Co-Authors: Luis Miguel Sender, James A. Doyle, Peter K Endress, Garland R. Upchurch, Uxue Villanuevaamadoz, José B. DiezAbstract:The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative pa...
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Evidence on vegetative and inflorescence morphology of Chloranthaceae (Angiospermae) from the Early Cretaceous (middle–late Albian) of Spain
Journal of Systematic Palaeontology, 2020Co-Authors: Luis Miguel Sender, James A. Doyle, Peter K Endress, Garland R. Upchurch, Uxue Villanueva-amadoz, José B. DiezAbstract:The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative pa...
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Phylogenetic Analyses of Cretaceous Fossils Related to Chloranthaceae and their Evolutionary Implications
The Botanical Review, 2018Co-Authors: James A. Doyle, Peter K EndressAbstract:Chloranthaceae were one of the first common lines during the early radiation of angiosperms, possibly reflecting adaptation to more open habitats. Phylogenetic analyses clarify the position of Cretaceous mesofossils in molecular trees of Recent taxa. Plants that produced Asteropollis pollen, with tepals adnate to a single carpel, are nested in crown group Chloranthaceae with Hedyosmum ; Canrightiopsis , with three stamens and no perianth, is sister to Sarcandra and Chloranthus ; and Canrightia is a stem relative that illustrates a still bisexual stage in floral reduction. Plants that produced Pennipollis pollen are related to Chloranthaceae and/or Ceratophyllum rather than monocots. Appomattoxia , which produced Tucanopollis pollen, has equivocal affinities, but Pseudoasterophyllites , with similar pollen and stems with reduced leaves, may be a link between Chloranthaceae and Ceratophyllum . These results imply that flowers became unisexual before losing the perianth, while bisexual flowers in Canrightiopsis , Sarcandra , and Chloranthus are secondarily derived from unisexual flowers.
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Ancestral traits and specializations in the flowers of the basal grade of living angiosperms
Taxon, 2015Co-Authors: James A. DoyleAbstract:© International Association for Plant Taxonomy (IAPT) 2015. New morphological and phylogenetic data prompt us to present an updated review of floral morphology and its evolution in the basal ANITA grade of living angiosperms, Chloranthaceae, and Ceratophyllum. Floral phyllotaxis is complex whorled in Nymphaeales and spiral in Amborella and Austrobaileyales. It is unresolved whether phyllotaxis was ancestrally whorled or spiral, but if it was whorled, the whorls were trimerous. The flowers are probably ancestrally bisexual because in most families with unisexual flowers these flowers exhibit rudiments of the opposite sex. Carpels are largely ascidiate and the closure line is short, either transverse or longitudinal. A style is usually absent or, if present, generally short and not plicate. Angiospermy (carpel sealing) is by secretion, rather than postgenital fusion, except in large-flowered Nymphaeales and in Illicium, correlated with unusual fruits. Carpels with a single, median, pendent ovule are probably plesiomorphic. Chloranthaceae and Ceratophyllaceae have an unsettled phylogenetic position, but in some phylogenetic analyses they form a clade, which may be sister to the remaining mesangiosperms (Magnoliidae, monocots, eudicots). This position is supported by their carpel characters, which are similar to those of the ANITA grade and different from those of most other mesangiosperms.
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reconstructing the ancestral angiosperm flower and its initial specializations
American Journal of Botany, 2009Co-Authors: Peter K Endress, James A. DoyleAbstract:: Increasingly robust understanding of angiosperm phylogeny allows more secure reconstruction of the flower in the most recent common ancestor of extant angiosperms and its early evolution. The surprising emergence of several extant and fossil taxa with simple flowers near the base of the angiosperms-Chloranthaceae, Ceratophyllum, Hydatellaceae, and the Early Cretaceous fossil Archaefructus (the last three are water plants)-has brought a new twist to this problem. We evaluate early floral evolution in angiosperms by parsimony optimization of morphological characters on phylogenetic trees derived from morphological and molecular data. Our analyses imply that Ceratophyllum may be related to Chloranthaceae, and Archaefructus to either Hydatellaceae or Ceratophyllum. Inferred ancestral features include more than two whorls (or series) of tepals and stamens, stamens with protruding adaxial or lateral pollen sacs, several free, ascidiate carpels closed by secretion, extended stigma, extragynoecial compitum, and one or several ventral pendent ovule(s). The ancestral state in other characters is equivocal: e.g., bisexual vs. unisexual flowers, whorled vs. spiral floral phyllotaxis, presence vs. absence of tepal differentiation, anatropous vs. orthotropous ovules. Our results indicate that the simple flowers of the newly recognized basal groups are reduced rather than primitively simple.
Xiaopo Zhang - One of the best experts on this subject based on the ideXlab platform.
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A new sesquiterpene lactone from Sarcandra glabra
Natural product research, 2012Co-Authors: Xiaopo Zhang, Jun-shan Yang, Zhong Dai, Rui-chao LinAbstract:A new eudesmanolide sesquiterpene, atractylenolide IV (1), together with seven known compounds were isolated from the 70% aqueous acetonic extract of the whole plant of Sarcandra glabra (Chloranthaceae). Their structures were established by spectral analysis, mainly UV, IR, HRESI-MS, 1D and 2D-NMR experiments (HSQC, HMBC and NOESY). Compounds 1–4 showed no remarkable cytotoxic activity against Hela, HCT-8 and MCF-7 cancer cell lines with IC50 > 50 µg mL−1.
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Isolation and chemotaxonomic significance of megastigmane-type sesquiterpenoids from Sarcandra glabra
Journal of Medicinal Plants Research, 2012Co-Authors: Xiaopo Zhang, Shilin Chen, Jun-shan YangAbstract:In this study, twelve known compounds including six megastigmane-type sesquiterpenoids, two coumarins and four phenols were isolated for the first time from Sarcandra glabra(Thunb.) Nakai, a traditional medicinal plant with a variety of pharmaceutical activities. Their structures were determined using nuclear magnetic resonance (NMR) and mass spectrometry (MS) techniques and the chemotaxonomic significance of megastigmane-type sesquiterpenoids was briefly discussed. Key words: Sarcandra glabra, Chloranthaceae, sesquiterpenoid, chemotaxonomy.
Rui-chao Lin - One of the best experts on this subject based on the ideXlab platform.
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A new sesquiterpene lactone from Sarcandra glabra
Natural product research, 2012Co-Authors: Xiaopo Zhang, Jun-shan Yang, Zhong Dai, Rui-chao LinAbstract:A new eudesmanolide sesquiterpene, atractylenolide IV (1), together with seven known compounds were isolated from the 70% aqueous acetonic extract of the whole plant of Sarcandra glabra (Chloranthaceae). Their structures were established by spectral analysis, mainly UV, IR, HRESI-MS, 1D and 2D-NMR experiments (HSQC, HMBC and NOESY). Compounds 1–4 showed no remarkable cytotoxic activity against Hela, HCT-8 and MCF-7 cancer cell lines with IC50 > 50 µg mL−1.