RESUMO
Four new γ-lactam alkaloids, suberitolactams A-D (1-4), two new pyridine alkaloids, suberitopyridines A-B (7-8), and two known compounds (5-6) were isolated from the South China Sea sponge Pseudospongosorites suberitoides. The structures were elucidated by detailed 1D and 2D NMR experiments along with HRESIMS analysis and single crystal X-ray diffraction. Compoundsâ 1 and 8 showed moderate to weak antiviral activity against H1â N1 virus with IC50 values of 27.6 and 13.3â µM, respectively.
Assuntos
Alcaloides , Antivirais , Lactamas , Poríferos , Piridinas , Animais , Alcaloides/isolamento & purificação , Alcaloides/química , Alcaloides/farmacologia , Poríferos/química , Lactamas/química , Lactamas/isolamento & purificação , Lactamas/farmacologia , Piridinas/química , Piridinas/isolamento & purificação , Piridinas/farmacologia , Antivirais/farmacologia , Antivirais/química , Antivirais/isolamento & purificação , China , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Cristalografia por Raios X , Estrutura Molecular , Conformação Molecular , Modelos MolecularesRESUMO
Six new fusarin derivatives, fusarins G-L (1-6), together with five known compounds (5-11) were isolated from the marine-derived fungus Fusarium solani 7227. The structures of the new compounds were elucidated by means of comprehensive spectroscopic methods (1D and 2D NMR, HRESIMS, ECD, and ORC) and X-ray crystallography. Compounds 5-11 exhibited potent anti-inflammatory activity by inhibiting the production of NO in RAW264.7 cells activated by lipopolysaccharide, with IC50 values ranging from 3.6 to 32.2 µM. The structure-activity relationships of the fusarins are discussed herein.
Assuntos
Anti-Inflamatórios/farmacologia , Fusarium , Lactamas/farmacologia , Óxido Nítrico/antagonistas & inibidores , Polienos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Fermentação , Fusarium/química , Fusarium/metabolismo , Lactamas/isolamento & purificação , Lipopolissacarídeos/farmacologia , Camundongos , Óxido Nítrico/metabolismo , Polienos/isolamento & purificação , Células RAW 264.7 , Metabolismo Secundário , Relação Estrutura-AtividadeRESUMO
Psammocindoles A-C (1-3), a new class of indole alkaloids, were isolated from a Psammocinia vermis sponge. By combined spectroscopic analyses, the structures of these compounds were determined to be the indole-γ-lactams derived from three amino acid residues. In addition, an enantiomer psammocindole D (4), and the N-lactam isomers isopsammocindoles A-D (5-8) were also synthesized. These natural products and synthetic analogues were found to significantly stimulate adiponectin secretion in human bone marrow mesenchymal stem cells.
Assuntos
Alcaloides Indólicos/química , Lactamas/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Poríferos/química , Animais , Produtos Biológicos , Humanos , Alcaloides Indólicos/isolamento & purificação , Lactamas/isolamento & purificação , Células-Tronco Mesenquimais/química , Estrutura Molecular , EstereoisomerismoRESUMO
Linariifolioside II (1) and (2S)-2-hydroxy-5-oxoproline methyl ester (2), two new compounds along with 13 known compounds were obtained from the aerial part of Pseudolysimachion linariifolium Holub subsp. dilatatum (Nakai & Kitag.) D.Y. Hong. Their chemical structures were revealed mainly through NMR and MS data. The absolute configuration of 2 was deduced by comparing its experimental CD with the calculated ECD spectra. At a concentration of 1â mm, total antioxidant capacities of compounds 1-15 were measured using a rapid ABTS method inâ vitro. Compounds 1, 3-5, and 11-14 exhibited approximately equal antioxidant capacity to that of vitamin C (Vc).
Assuntos
Antioxidantes/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Lactamas/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Veronica/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Benzotiazóis/antagonistas & inibidores , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Lactamas/química , Lactamas/isolamento & purificação , Medicina Tradicional Chinesa , Estrutura Molecular , Fenóis/química , Fenóis/isolamento & purificação , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Ácidos Sulfônicos/antagonistas & inibidoresRESUMO
With a combined strategy of bioinformatics analysis, gene manipulation coupled with variation of growth conditions, the targeted activation of polycyclic tetramate macrolactams (PTMs) in the deepsea-derived Streptomyces somaliensis SCSIO ZH66 was conducted, which afforded a new (1) PTM, named somamycin A, along with three enol-type tetramic acid tautomers (2-4, somamycins B-D) of 10-epi-hydroxymaltophilin, 10-epi-maltophilin and 10-epi-HSAF, respectively. The structures of compounds 1-4 were elucidated by extensive spectroscopic analyses together with ECD calculations. Compound 1 exhibited notable growth inhibition against plant pathogenic fungi Fusariumoxysporum MHKW and Alternariabrassicae BCHB with the MIC values of 1.6 and 3.1 µg/mL, respectively, which were more potent than those of the positive control nystatin; and compounds 3 and 4 displayed moderate antifungal activities. Moreover, compounds 1-4 exhibited moderate cytotoxicity against the human cancer cell lines of HCT116 and K562.
Assuntos
Lactamas/isolamento & purificação , Compostos Policíclicos/isolamento & purificação , Água do Mar/microbiologia , Streptomyces/química , Análise Espectral/métodosRESUMO
Four new phenylspirodrimane-type dimers, namely chartarlactams Q-T, along with stachyin B were isolated from the fermentation broth of a sponge-derived fungus Stachybotrys chartarum WGC-25â C-6. Chartarlactams Q-T were structurally featured by the dimerization of two units of phenylspirodrimane linked by a C-N bond. Their structures were determined on the basis of extensive spectroscopic analysis, while quantum ECD calculation and modified Mosher's method were used for the assignment of absolute configurations. Chartarlactams Q-S and stachyin B showed moderate inhibition against bacterial pathogen Staphylococcus aureus with MIC values ranging from 4 µg/mL to 16 µg/mL, and chartarlactam T exhibited significant inhibition toward ZIKV virus.
Assuntos
Antibacterianos/química , Antivirais/química , Lactamas/química , Sesquiterpenos Policíclicos/química , Stachybotrys/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antivirais/isolamento & purificação , Antivirais/farmacologia , Dicroísmo Circular , Dimerização , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lactamas/isolamento & purificação , Lactamas/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Conformação Molecular , Sesquiterpenos Policíclicos/isolamento & purificação , Sesquiterpenos Policíclicos/farmacologia , Stachybotrys/metabolismo , Zika virus/efeitos dos fármacosRESUMO
Chemical investigation of the mangrove endophytic fungus Cladosporium sp. SCNU-F0001 resulted in the isolation and identification of a new macrolide compound named thiocladospolide E (1) and a novel macrolide lactam named cladospamide A (2), along with the known cladospolide B (3). The structures were elucidated based on spectroscopic methods, and the absolute configurations were determined by X-ray diffraction and HPLC analysis after chemical derivatization. All compounds were tested for their antibacterial and cytotoxic activity.
Assuntos
Antibacterianos/farmacologia , Cladosporium/química , Lactamas/farmacologia , Macrolídeos/farmacologia , Rhizophoraceae/microbiologia , Antibacterianos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Lactamas/isolamento & purificação , Macrolídeos/isolamento & purificação , Estrutura MolecularRESUMO
Three new polycyclic macrolactams, cyclamenols B-D (1-3), together with a known macrolactam, cyclamenol A (4), were isolated from the Streptomyces sp. OUCMDZ-4348. Their structures including absolute configurations were determined on the basis of spectroscopic analysis, chemical methods, and ECD calculations. The biosynthetic pathways involving intramolecular Diels-Alder reactions were proposed. Compound 1 exhibited selective inhibition against the gastric carcinoma cell line N87 with an IC50 value of 10.8 µM.
Assuntos
Lactamas Macrocíclicas/metabolismo , Lactamas/metabolismo , Streptomyces/química , Regiões Antárticas , Reação de Cicloadição , Lactamas/química , Lactamas/isolamento & purificação , Lactamas Macrocíclicas/química , Lactamas Macrocíclicas/isolamento & purificação , Modelos Moleculares , Conformação Molecular , Especificidade da EspécieRESUMO
Three new 12- or 13-membered-ring macrocyclic alkaloids, named ascomylactams A-C (1-3), along with the analogues phomapyrrolidone C (4) and phomapyrrolidone A (5) were isolated from the mangrove endophytic fungus Didymella sp. CYSK-4. Their structures were elucidated by analysis of extensive spectroscopic data and mass spectrometric data. The structures and absolute configurations of 1 and 2 were determined by single-crystal X-ray diffraction experiments, which represents the first crystal structures described for a (6/5/6/5) tetracyclic skeleton fused with a 12- or 13-membered-ring macrocyclic moiety. The configurations of phomapyrrolidone C (4) and phomapyrrolidone A (5) were revised by detailed analysis of the NMR data. In a cytotoxic assay, compounds 1 and 3 showed moderate cytotoxicity against MDA-MB-435, MDA-MB-231, SNB19, HCT116, NCI-H460, and PC-3 human cancer cell lines, with IC50 values in the range of 4.2-7.8 µM.
Assuntos
Alcaloides/química , Ascomicetos/química , Lactamas/química , Lactamas/isolamento & purificação , Compostos Macrocíclicos/química , Rhizophoraceae/microbiologia , Alcaloides/isolamento & purificação , Ascomicetos/isolamento & purificação , Estrutura MolecularRESUMO
In our screening program for new biologically active secondary metabolites, a new strain, Nocardiopsis CG3 (DSM 106572), isolated from the saltpan of Kenadsa, was found to produce five new polyene macrolactams, the kenalactams A-E (1-5). Their structures were elucidated by spectral methods (NMR and HRESIMS), and the absolute configuration was derived by chemical derivatization (Mosher's method). Through a feeding experiment, alanine was proven to be the nitrogen-bearing starter unit involved in biosynthesis of the polyketide kenalactam A (1). Kenalactam E (5) was cytotoxic against human prostate cancer PC-3 cells with an IC50 value of 2.1 µM.
Assuntos
Actinobacteria/química , Lactamas/isolamento & purificação , Polienos/isolamento & purificação , Linhagem Celular Tumoral , Humanos , Lactamas/química , Lactamas/farmacologia , Polienos/química , Polienos/farmacologia , Policetídeos/química , Policetídeos/isolamento & purificação , Policetídeos/farmacologiaRESUMO
A sponge-associated actinomycete (strain MCCB267) was isolated from a marine sponge Mycale sp. collected in the Indian Ocean off the Southeast coast of India. Phylogenetic studies of this strain using 16S rRNA gene sequencing showed high sequence similarity to Streptomyces zhaozhouensis. However, strain MCCB267 showed distinct physiological and biochemical characteristic features and was thus designated as S. zhaozhouensis subsp. mycale. subsp. nov. A cytotoxicity-guided fractionation of the crude ethyl acetate extract of strain MCCB267 culture medium yielded four pure compounds belonging to the polycyclic tetramate macrolactam (PTM) family of natural products: ikarugamycin (IK) (1), clifednamide A (CF) (2), 30-oxo-28-N-methylikarugamycin (OI) (3), and 28-N-methylikarugamycin (MI) (4). The four compounds exhibited promising cytotoxic activity against NCI-H460 lung carcinoma cells in vitro, by inducing cell death via apoptosis. Flow cytometric analysis revealed that 1, 3, and 4 induced cell cycle arrest during G1 phase in the NCI-H460 cell line, whereas 2 induced cell arrest in the S phase. A concentration-dependent accumulation of cells in the sub-G1 phase was also detected upon treatment of the cancer cell line with compounds 1-4. The in vitro cytotoxicity studies were supported by molecular docking and molecular dynamic simulation analyses. An in silico study revealed that the PTMs can bind to the minor groove of DNA and subsequently induce the apoptotic stimuli leading to cell death. The characterization of the isolated actinomycete, the study of the mode of action of the four PTMs, 1-4, and the molecular docking and molecular dynamic simulations analyses are herein described.
Assuntos
Antineoplásicos/química , Apoptose/efeitos dos fármacos , DNA/química , Lactamas Macrocíclicas/química , Lactamas/química , Streptomyces/química , Animais , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Apoptose/genética , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/genética , Humanos , Concentração Inibidora 50 , Lactamas/isolamento & purificação , Lactamas/farmacologia , Lactamas Macrocíclicas/isolamento & purificação , Lactamas Macrocíclicas/farmacologia , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Filogenia , Poríferos/microbiologia , Poríferos/fisiologia , RNA Ribossômico 16S/genética , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase S do Ciclo Celular/genética , Streptomyces/classificação , Streptomyces/metabolismo , Simbiose/fisiologiaRESUMO
A new lactam, oligoamide (1), along with three known compounds (2-4), stigmasterol-3-O-ß-D-glucopyranoside (2), formononetin (3) and (-)-pinitol (4) were isolated from the CH2Cl2/CH3OH (1:1) extract of the leaves of Angylocalyx oligophyllus by chromatographic separation. Their structures were elucidated on the basis of spectroscopic analysis (UV, IR, MS, 1D, and 2D NMR). Compound 1 was found to have weak antioxidant and urease inhibitory potential.
Assuntos
Fabaceae/química , Lactamas/isolamento & purificação , Folhas de Planta/química , Antioxidantes/química , Antioxidantes/isolamento & purificação , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Lactamas/química , Estrutura Molecular , Análise Espectral , Urease/antagonistas & inibidoresRESUMO
From an EtOAc-soluble fraction of the leaves of Azadirachta indica, one new lactam 28-norlimonoid named nimbandiolactam-21 (1), together with 2 known limonoids (2 and 3) were isolated. Their relative structures were elucidated based on NMR spectroscopic analysis. Nimbandiolactone-23 (2) showed the most potent α-glucosidase inhibitory activity, with an IC50 value of 38.7 µM. Compound 1 represents the first naturally occurring example of a 28-norlimonoid having the lactam moiety. The plausible biosynthetic pathway for the formation of lactam moiety in 1 was proposed.
Assuntos
Azadirachta/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Lactamas/farmacologia , Limoninas/farmacologia , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Concentração Inibidora 50 , Lactamas/química , Lactamas/isolamento & purificação , Limoninas/química , Limoninas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Folhas de Planta/química , Plantas Medicinais/químicaRESUMO
In search for novel antiseizure drugs (ASDs), the European FP7-funded PharmaSea project used zebrafish embryos and larvae as a drug discovery platform to screen marine natural products to identify promising antiseizure hits in vivo for further development. Within the framework of this project, seven known heterospirocyclic γ-lactams, namely, pseurotin A, pseurotin A2, pseurotin F1, 11- O-methylpseurotin A, pseurotin D, azaspirofuran A, and azaspirofuran B, were isolated from the bioactive marine fungus Aspergillus fumigatus, and their antiseizure activity was evaluated in the larval zebrafish pentylenetetrazole (PTZ) seizure model. Pseurotin A2 and azaspirofuran A were identified as antiseizure hits, while their close chemical analogues were inactive. Besides, electrophysiological analysis from the zebrafish midbrain demonstrated that pseurotin A2 and azaspirofuran A also ameliorate PTZ-induced epileptiform discharges. Next, to determine whether these findings translate to mammalians, both compounds were analyzed in the mouse 6 Hz (44 mA) psychomotor seizure model. They lowered the seizure duration dose-dependently, thereby confirming their antiseizure properties and suggesting activity against drug-resistant seizures. Finally, in a thorough ADMET assessment, pseurotin A2 and azaspirofuran A were found to be drug-like. Based on the prominent antiseizure activity in both species and the drug-likeness, we propose pseurotin A2 and azaspirofuran A as lead compounds that are worth further investigation for the treatment of epileptic seizures. This study not only provides the first evidence of antiseizure activity of pseurotins and azaspirofurans, but also demonstrates the value of the zebrafish model in (marine) natural product drug discovery in general, and for ASD discovery in particular.
Assuntos
Anticonvulsivantes/farmacologia , Lactamas/farmacologia , Pirrolidinonas/farmacologia , Compostos de Espiro/farmacologia , Animais , Anticonvulsivantes/química , Anticonvulsivantes/isolamento & purificação , Aspergillus fumigatus , Encéfalo/efeitos dos fármacos , Linhagem Celular , Descoberta de Drogas , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Estimulação Elétrica , Humanos , Oceano Índico , Lactamas/química , Lactamas/isolamento & purificação , Masculino , Camundongos , Estrutura Molecular , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Distribuição Aleatória , Convulsões/tratamento farmacológico , Compostos de Espiro/química , Compostos de Espiro/isolamento & purificação , Peixe-ZebraRESUMO
Chemical investigation of two Irciniidae sponges collected by hand (SCUBA) from Australian near shore waters, afforded six new examples of a rare class of sesterterpene lactam; ircinialactams B (1), G (2), H (5), and I (6), and 8-hydroxyircinialactams C (3) and G (4); together with the new biosynthetically related lactone, ircinialactone A (7). Also isolated were seven biosynthetically related known Irciniidae metabolites; ircinialactams A (8) and C (9), (7E,12E,20Z,18S)-variabilin (10), (7Z,12Z,20Z,18S)-variabilin (11), (7E,12Z,20Z,18S)-variabilin (12), (7Z,12E,20Z,18S)-variabilin (13) and irciniafuran A (14). The structure elucidation of 1-14 was achieved by detailed spectroscopic analysis, and consideration of a plausible biosynthetic relationship linking Irciniidae sesterterpene ß-furans, lactams and lactones.
Assuntos
Lactamas/química , Poríferos/química , Sesterterpenos/química , Animais , Lactamas/isolamento & purificação , Estrutura Molecular , New South Wales , Proteínas/química , Sesterterpenos/isolamento & purificaçãoRESUMO
A pair of enantiomeric 4-oxabicyclic[4.3.0]lactam derivatives, (+)- and (-)-penicilactam A (1), and one new polyketide derivative penicitrinone F (2) were isolated from the marine-derived fungus Penicillium griseofulvum GT-10. Their structures and absolute configurations were elucidated through extensive spectroscopic analyses combined with the calculated ECD spectra. Penicitrinone F (2) had moderate inhibitory activity towards Bacillus subtilis with a MIC value of 6.3 µM.
Assuntos
Lactamas/química , Penicillium/química , Policetídeos/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Citrinina/análogos & derivados , Citrinina/isolamento & purificação , Lactamas/isolamento & purificação , Estrutura Molecular , Policetídeos/isolamento & purificação , Pironas/química , Pironas/isolamento & purificação , Análise EspectralRESUMO
Eight new γ-lactam alkaloids, hemerominors A-H (1-8), including two pair of epimers (1-4), together with six known compounds (9-14) were isolated from the roots of Hemerocallis minor Mill. The structures of 1-8 were established on the basis of extensive NMR studies and HR-MS measurements as well as comparison with literature data. The absolute configurations of 1-8 were determined by CD spectral analysis and modified Mosher's method. All of compounds were evaluated for their inhibitory effects against LPS-induced NO production in RAW264.7 macrophages. Among them, compound 13 exhibited moderate inhibitory activity against NO production and with IC50 value of 18.0 µM.
Assuntos
Alcaloides/química , Hemerocallis/química , Lactamas/química , Alcaloides/isolamento & purificação , Animais , Lactamas/isolamento & purificação , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico , Raízes de Plantas/química , Células RAW 264.7RESUMO
In the search for new antiprotozoal substances, hoshinolactam, an antitrypanosomal lactam, was isolated from a marine cyanobacterium. The gross structure was elucidated by spectroscopic analyses, and the absolute configuration was determined by the first total synthesis. Hoshinolactam showed potent antitrypanosomal activity with an IC50 value of 3.9 nM without cytotoxicity against human fetal lung fibroblast MRC-5 cells (IC50 > 25 µM).
Assuntos
Cianobactérias/química , Lactamas/síntese química , Lactamas/isolamento & purificação , Tripanossomicidas/síntese química , Tripanossomicidas/isolamento & purificação , Organismos Aquáticos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Concentração Inibidora 50 , Pulmão/citologia , EstereoisomerismoRESUMO
Chemical investigation of Tamarix ramosissima Ledeb, a traditional herbal medicine used for rheumatoid arthritis (RA) treatment in northwest China, led to the discovery of a new phenolic aromatic rings substituted lactam, tamaractam (1), together with the previously reported compounds cis-N-feruloyl-3-O-methyldopamine (2) and trans-N-feruloyl-3-O-methyldopamine (3). The structures of the compounds were determined by high resolution electrospray ionization mass spectroscopy (HRESIMS) and 1D and 2D-NMR experiments, as well as comparison with the literature data. The effects of the three compounds on the viability of RA fibroblast-like synoviocytes (RA-FLS) were assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Pro-apoptosis effect of compound 1 in RA-FLS was further investigated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay, activated caspase-3/7 level assessment using luminescence assay, and sub-G1 fraction measurement using flow cytometry. It was found that these three compounds displayed variable proliferation inhibitory activity in RA-FLS, and compound 1 exhibited the strongest effect. Compound 1 could remarkably induce cellular apoptosis of RA-FLS, increase activated caspase-3/7 levels, and significantly increase sub-G1 fraction in the cell cycle. The results suggested that compound 1 may inhibit the proliferation of RA-FLS through apoptosis-inducing effect, and these compounds may contribute to the anti-RA effect of T. ramosissima.
Assuntos
Apoptose/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Desoxiepinefrina/química , Lactamas/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Desoxiepinefrina/análogos & derivados , Desoxiepinefrina/farmacologia , Fibroblastos/efeitos dos fármacos , Humanos , Lactamas/isolamento & purificação , Lactamas/farmacologia , Medicina Tradicional Chinesa , Sinoviócitos/efeitos dos fármacos , Tamaricaceae/químicaRESUMO
Monascustin (1), an unusual γ-lactam, was isolated from an ethanol extract of the Monascus purpureus fermented rice. Its structure including the absolute configuration was determined by spectroscopic data analysis and confirmed by X-ray crystallography. A plausible biosynthetic pathway is discussed on the basis of amino acid derivatization. Compound 1 showed inhibitory activity against histone deacetylase 1.