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Phytochemistry May 2011A rare 16β-H steroidal alkaloid saponin (1), an avenacoside-type saponin (2), two steroidal saponins (4, 5), one revised-structure steroidal saponin (3) and six known...
A rare 16β-H steroidal alkaloid saponin (1), an avenacoside-type saponin (2), two steroidal saponins (4, 5), one revised-structure steroidal saponin (3) and six known compounds (6-11) were isolated from aerial parts of Solanum surattense Burm. f. Their structures were established on the basis of physical data, as well as by using spectroscopic (HRESIMS, 1D and 2D NMR), and chemical analysis methods. Compounds 1 and 11 showed cytotoxicity against A549 cell line with IC(50) values of 20.3 and 15.7μM, respectively.
Topics: Alkaloids; Cell Line, Tumor; Humans; Inhibitory Concentration 50; Saponins; Solanum
PubMed: 21334700
DOI: 10.1016/j.phytochem.2011.01.028 -
Journal of Zhejiang University.... Dec 2013Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such...
Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from all six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were observed both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R(2)=0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding.
Topics: Alkaloids; Genetic Variation; Plant Leaves; Tissue Distribution; Nicotiana
PubMed: 24302710
DOI: 10.1631/jzus.B1300130 -
Zhongguo Zhong Yao Za Zhi = Zhongguo... Jul 2015The genus Nodulisporium, is known to produce secondary metabolites with structural diversity. A new alkaloid, 2-hy-...
The genus Nodulisporium, is known to produce secondary metabolites with structural diversity. A new alkaloid, 2-hy- droxy-1,1-dimethyl-1,2,3,9-tetrahydro-4H-carbazol-4-one(1), was isolated from the extract of a fungal strain Nodulisporium sp. fermented with rice, together with three known phenols, tyrosol(2), hydroxytyrosol(3), and hydroxytyrosol acetate(4). Their structures were identified by detailed spectroscopic analyses.
Topics: Alkaloids; Xylariales
PubMed: 26697685
DOI: No ID Found -
Journal of Natural Products Apr 2023The monoterpene indole alkaloid (MIA) mitragynine has garnered attention as a potential treatment for pain, opioid use disorder, and opioid withdrawal because of its...
The monoterpene indole alkaloid (MIA) mitragynine has garnered attention as a potential treatment for pain, opioid use disorder, and opioid withdrawal because of its combined pharmacology at opioid and adrenergic receptors in humans. This alkaloid is unique to (kratom), which accumulates over 50 MIAs and oxindole alkaloids in its leaves. Quantification of 10 targeted alkaloids from several tissue types and cultivars of revealed that mitragynine accumulation was highest in leaves, followed by stipules and stems, but was absent, along with other alkaloids, in roots. While mitragynine is the predominant alkaloid in mature leaves, juvenile leaves accumulate higher amounts of corynantheidine and speciociliatine. Interestingly, corynantheidine has an inverse relationship with mitragynine accumulation throughout leaf development. Characterization of various cultivars of indicated altered alkaloidal profiles ranging from undetectable to high levels of mitragynine. DNA barcoding and phylogenetic analysis using ribosomal sequences revealed polymorphisms leading cultivars having lower mitragynine content to group with other mitragyna species, suggesting interspecific hybridization events. Root transcriptome analysis of low- and high-mitragynine-producing cultivars indicated significant differences in gene expression and revealed allelic variation, further supporting that hybridization events may have impacted the alkaloid profile of .
Topics: Humans; Mitragyna; Analgesics, Opioid; Oxindoles; Phylogeny; Secologanin Tryptamine Alkaloids; Indoles
PubMed: 36913648
DOI: 10.1021/acs.jnatprod.3c00092 -
The Journal of Organic Chemistry Feb 2015The loline alkaloids present a compact polycyclic pyrrolizidine skeleton and contain a strained five-membered ethereal bridge, structural features that have proven...
The loline alkaloids present a compact polycyclic pyrrolizidine skeleton and contain a strained five-membered ethereal bridge, structural features that have proven challenging for synthetic chemists to incorporate since the discovery of this natural product family more than 100 years ago. These alkaloids are produced by mutualistic fungal symbionts (endophytes) living on certain species of pasture grasses and protect the host plant from insect herbivory. The asymmetric total synthesis of loline alkaloids is reported and extends our first-generation (racemic) synthesis of this alkaloid family. Key to the synthesis is a diastereoselective tethered aminohydroxylation of a homoallylic carbamate function and a Petasis Borono-Mannich addition.
Topics: Alkaloids; Biochemical Phenomena; Carbamates; Fungi; Molecular Structure; Polycyclic Compounds
PubMed: 25611615
DOI: 10.1021/jo502493e -
Medicinal Chemistry (Shariqah (United... 2020Matrine-family alkaloids as tetracycloquinolizindine analogues from Traditional Chinese Medicine Sophora flavescens Ait, Sophora subprostrata and Sophora alopecuroides L... (Review)
Review
Matrine-family alkaloids as tetracycloquinolizindine analogues from Traditional Chinese Medicine Sophora flavescens Ait, Sophora subprostrata and Sophora alopecuroides L possess various pharmacological activities and have aroused great interests over the past decades. Especially, a lot of matrine derivatives have been designed and synthesized and their biological activities investigated, and encouraging results have continuously been achieved in recent several years. These studies are helpful to develop more potent candidates or therapeutic agents and disclose their molecular targets and mechanisms. This paper reviews recent advances in the bioactive modifications of matrine-family alkaloids from derivatization of the C-13, C-14 or C-15 position, opening D ring, fusing D ring and structural simplification.
Topics: Alkaloids; Drug Discovery; Humans; Quinolizines; Structure-Activity Relationship; Matrines
PubMed: 31378199
DOI: 10.2174/1573406415666190507121744 -
Bioorganic Chemistry Jun 2021To date, Alzheimer's disease is the most alarming neurodegenerative disorder worldwide. This illness is multifactorial in nature and cholinesterase inhibitors have been...
To date, Alzheimer's disease is the most alarming neurodegenerative disorder worldwide. This illness is multifactorial in nature and cholinesterase inhibitors have been the ones used in clinical treatments. In this context, many of these drugs selectively inhibit the acetylcholinesterase enzyme interacting in both the active site and the peripheric anionic site. Besides, some agents have exhibited extensive benefits being able to co-inhibit butyrylcholinesterase. In this contribution, a strategy previously explored by numerous authors is reported; the synthesis of hybrid cholinesterase inhibitors. This strategy uses a molecule of recognized high inhibitory activity (tacrine) together with a steroidal alkaloid of natural origin using different connectors. The biological assays demonstrated the improvement in the inhibitory activity compared to the alkaloidal precursor, together with the reinforcement of the interactions in multiple sites of the enzymatic cavity. This strategy should be explored and exploited in this area. Docking and molecular dynamic studies were performed to explain enzyme-ligand interactions, assisting a structure-activity relationship analysis.
Topics: Acetylcholinesterase; Alkaloids; Animals; Biological Products; Butyrylcholinesterase; Cholinesterase Inhibitors; Dose-Response Relationship, Drug; Drug Design; Electrophorus; Horses; Molecular Structure; Steroids; Structure-Activity Relationship
PubMed: 33882364
DOI: 10.1016/j.bioorg.2021.104893 -
Journal of Chemical Ecology Apr 2015Social parasites exploit other societies by invading and stealing resources. Some enter protected nests using offensive chemical weaponry made from alkaloid-based venom....
Social parasites exploit other societies by invading and stealing resources. Some enter protected nests using offensive chemical weaponry made from alkaloid-based venom. We characterized the venoms of three Megalomyrmex thief ant species (M. mondabora, M. mondaboroides, and M. silvestrii) that parasitize the fungus-growing ants, and developed an ethogram to describe host ant reactions to raiding M. mondaboroides and M. silvestrii parasites. We compared piperidine, pyrrolidine, and pyrolizidine venom alkaloid structures with synthetic samples from previous studies, and describe the novel stereochemistry of trans 2-hexyl-5-[8-oxononyl]-pyrrolidine (3) from M. mondabora. We showed that workers of Cyphomyrmex costatus, the host of M. mondaboroides and M. silvestrii, react to a sting by Megalomyrmex parasites mainly with submissive behavior, playing dead or retreating. Host submission also followed brief antennal contact. The behavior of C. costatus ants observed in this study was similar to that of Cyphomyrmex cornutus, host of M. mondabora, suggesting that the alkaloidal venoms with pyrrolidines from M. mondabora, piperidines from M. mondaboroides, and pyrolizidines from M. silvestrii may function similarly as appeasement and repellent allomones against host ants, despite their different chemical structure. With the use of these chemical weapons, the Megalomyrmex thief ants are met with little host resistance and easily exploit host colony resources.
Topics: Alkaloids; Animals; Ant Venoms; Ants; Species Specificity
PubMed: 25833216
DOI: 10.1007/s10886-015-0565-y -
Natural Product Research Jun 2004A new dehydroaporphine alkaloid (-)-6a,7-dehydrofloripavidine has been isolated from the aerial parts of Papaver fugax Poir. (Papaveraceae) collected from Erzurum...
A new dehydroaporphine alkaloid (-)-6a,7-dehydrofloripavidine has been isolated from the aerial parts of Papaver fugax Poir. (Papaveraceae) collected from Erzurum (Eastern Anatolia). (-)-Floripavidine (aporphine) and (-)-mecambrine (proaporphine) were isolated as major alkaloids. Other bases present were (+)-salutaridine (promorphinane) and argentinine (phenanthrene). The presence of argentinine has been shown for the first time in the Papaveraceae.
Topics: Alkaloids; Aporphines; Papaver; Plant Leaves
PubMed: 15143838
DOI: 10.1080/14786410310001608154 -
The Plant Cell May 2022Polyamines are important metabolites in plant development and abiotic and biotic stress responses. Copper-containing amine oxidases (CuAOs) are involved in the...
Insights into polyamine metabolism: homospermidine is double-oxidized in two discrete steps by a single copper-containing amine oxidase in pyrrolizidine alkaloid biosynthesis.
Polyamines are important metabolites in plant development and abiotic and biotic stress responses. Copper-containing amine oxidases (CuAOs) are involved in the regulation of polyamine levels in the cell. CuAOs oxidize primary amines to their respective aldehydes and hydrogen peroxide. In plants, aldehydes are intermediates in various biosynthetic pathways of alkaloids. CuAOs are thought to oxidize polyamines at only one of the primary amino groups, a process frequently resulting in monocyclic structures. These oxidases have been postulated to be involved in pyrrolizidine alkaloid (PA) biosynthesis. Here, we describe the identification and characterization of homospermidine oxidase (HSO), a CuAO of Heliotropium indicum (Indian heliotrope), involved in PA biosynthesis. Virus-induced gene silencing of HSO in H. indicum leads to significantly reduced PA levels. By in vitro enzyme assays after transient in planta expression, we show that this enzyme prefers Hspd over other amines. Nuclear magnetic resonance spectroscopy and mass spectrometry analyses of the reaction products demonstrate that HSO oxidizes both primary amino groups of homospermidine (Hspd) to form a bicyclic structure, 1-formylpyrrolizidine. Using tracer feeding, we have further revealed that 1-formylpyrrolizidine is an intermediate in the biosynthesis of PAs. Our study therefore establishes that HSO, a canonical CuAO, catalyzes the second step of PA biosynthesis and provides evidence for an undescribed and unusual mechanism involving two discrete steps of oxidation that might also be involved in the biosynthesis of complex structures in other alkaloidal pathways.
Topics: Aldehydes; Amine Oxidase (Copper-Containing); Oxidation-Reduction; Polyamines; Pyrrolizidine Alkaloids
PubMed: 35212762
DOI: 10.1093/plcell/koac068