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1.
Along with the alkaloïds (+)spectaline (1) and (?)iso-6-cassine (2), two new piperidinol alkaloïds have been isolated from the seeds of Cassia spectabilis DC. They have been shown to possess structures 3 and 4 through chemical and spectral studies. 相似文献
2.
Shi-Fei Li Ying-Tong DiHong-Ping He Yu ZhangYue-Hu Wang Jun-Lin Yin Cheng-Jian TanShun-Lin Li Xiao-Jiang Hao 《Tetrahedron letters》2011,52(25):3186-3188
Two novel alkaloids, trigonoine A containing a 2,8-diazabicyclo[3.3.1]nonane ring system and trigonoine B formed by a combination of a 2,3-dihydroquinolin-4-one and 3H-pyrrolo[2,3-c]quinoline rearranged from β-carboline skeleton were isolated from the leaves of Trigonostemon lii. Their structures were elucidated by 1D and 2D NMR spectroscopic methods. 相似文献
3.
Koichiro Koyama Yusuke Hirasawa Tomohiro Hoshino Norimichi Nakahata 《Tetrahedron》2005,61(15):3681-3690
Seven new Lycopodium alkaloids, lannotinidines A-G (1-7), have been isolated from the club moss Lycopodium annotinum and L. annotinum var. acrifolium. Stereochemistry of 1-7 was elucidated by combination of NOESY correlations and chemical transformation. Lannotinidines B-E (2-5) elevated NGF mRNA expression. 相似文献
4.
Yanhui Fu Hongping HeYingtong Di Shunlin LiYu Zhang Xiaojiang Hao 《Tetrahedron letters》2012,53(28):3642-3646
Mekongenine A (1) possessing an unprecedented structure constituted from the union of a rare 2,7-seco eburnamine half and an aspidospermine alkaloid, together with a new bisindole alkaloid, mekongenine B (2), consisting of an eburnamine-aspidospermine type skeleton, was isolated from Bousigonia mekongensis. Their structures were elucidated by means of spectroscopic methods and those of 2 were further confirmed by X-ray diffraction. The absolute configurations of 1 and 2 were determined by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. Mekongenines A (1) and B (2) exhibited cell growth inhibitory activities against various human cancer cell lines. 相似文献
5.
A new dimer of C16N2 type alkaloid, complanadine B (1), and two new C16N type alkaloids, obscurumines A (2) and B (3), have been isolated from the club moss Lycopodium complanatum and L. obscurum, respectively. The structures and stereochemistry of 1-3 were elucidated by combination of 2D NMR spectra and chemical transformation. Complanadine A (4) isolated together with 1 induced secretion of neurotrophic factors from human astrocytoma cells. 相似文献
6.
Daphtenidines A-D (1-4), four new alkaloids were isolated from the leaves of Daphniphyllum teijsmannii, and the structures including relative stereochemistry were elucidated on the basis of spectroscopic data. Daphtenidines A (1) and B (2) were possessing daphnilactone A-type skeleton. This is the second isolation of daphnilactone A-type alkaloids from natural sources. Daphtenidine C (3) was 4-acetoxy form of daphmanidin A, while daphtenidine D (4) was 14-dehydro form of yuzurimine. 相似文献
7.
Six new Daphniphyllum alkaloids, calyciphyllines H-M (1-6), were isolated from the leaves and stems of Daphniphyllum calycinum (Daphniphyllaceae). The structures and relative stereochemistry of 1-6 were elucidated on the basis of spectroscopic data, and the absolute stereochemistry of 3 was assigned by PGME method. 相似文献
8.
Wisanu ManeeratThunwadee Ritthiwigrom Sarot CheenprachaUma Prawat Surat Laphookhieo 《Tetrahedron letters》2011,52(26):3303-3305
Two new dimeric carbazole alkaloids, clausenawallines A and B, were isolated from the roots of Clausena wallichii. Their structures were elucidated by spectroscopic methods. Clausenawalline A was evaluated for its biological activities [anti-malaria (IC50 2.46 μg/mL), anti-TB (MIC 12.50 μg/mL)] and cytotoxicity against three human cancer cell lines [KB (IC50 7.87 μg/mL), MCF7 (IC50 25.43 μg/mL), and NCI-H187 (IC50 10.97 μg/mL)]. 相似文献
9.
Chemical investigation of the crude base of Pandanus dubius led to the isolation of two new alkaloids, dubiusamine-A (1) and dubiusamine-B (2). The structures of the two alkaloids including their absolute configuration were unambiguously confirmed by 1D and 2D NMR analysis and asymmetric total synthesis. 相似文献
10.
Hongwei Liu Takeshi Fujiwara Yuri Mishima Takeshi Shida Hisayoshi Kobayashi Michio Namikoshi 《Tetrahedron》2005,61(36):8611-8615
Three new polysulfur alkaloids, lissoclibadins 1 (1)-3 (3), were isolated from the ascidian Lissoclinum sp. (cf. L. badium Monniot, F. and Monniot, C., 1996). The structures of 1-3 were assigned on the basis of their spectral data, and the computational modeling study was utilized for 1. Compound 1 had a trimeric structure of three identical aromatic anime moieties connected through two sulfide and a disulfide bonds. Compounds 2 and 3 were dimeric structures of the same unit as that of 1 connected through a sulfide and disulfide bonds (2) and two sulfide bonds (3). Compounds 1 and 2 inhibited the growth of the marine bacterium Ruegeria atlantica (15.2 mm at 20 μg/disk and 12.2 mm at 5 μg/disk, respectively) and 2 showed antifungal activity to Mucor hiemalis (13.8 mm at 50 μg/disk). Compounds 1-3 were cytotoxic against HL-60 (IC50=0.37, 0.21, and 5.5 μM, respectively). 相似文献
11.
Kan’ichiro IshiuchiTakaaki Kubota Haruaki IshiyamaShigeki Hayashi Toshiro ShibataJun’ichi Kobayashi 《Tetrahedron letters》2011,52(2):289-292
New Lycopodium alkaloids, lyconadins C (1) and F (2), were isolated from the club moss Lycopodium complanatum. Lyconadin C (1) is a new C16N2-type Lycopodium alkaloid possessing unique fused-tetracyclic ring system consisting of a cycloheptene ring fused to a decahydroquinoline and pyridone rings. Lyconadin F (2) possesses a primary amide moiety in its molecular, which is the first example of Lycopodium alkaloids. Biogenetically, lyconadins C (1) and F (2) might be related to lyconadins A (4) and B (5). The structures and relative stereochemistry of 1 and 2 were elucidated on the basis of spectroscopic data. The absolute stereochemistry of 2 was elucidated by chemical correlations with lyconadin B (5) through hemiaminal form of lyconadin F (3). 相似文献
12.
Zha-Jun Zhan 《Tetrahedron》2005,61(46):11038-11045
Six new Daphniphyllum alkaloids, namely caldaphnidines A-F (1-6), together with eight known ones, deoxycalyciphylline B, deoxyisocalyciphylline B, bukittiggine, calycicine A, methyl homosecodaphniphyllate, daphnilactone B, and daphnezomines L-M, were isolated from the leaves and the seeds of Daphniphyllum calycinum. The structure of 1 was determined by a single-crystal X-ray diffraction study, and the structures of 2-6 were established by spectral methods, especially two-dimensional NMR techniques (1H-1H COSY, HMQC, HMBC, and NOESY). 相似文献
13.
Yang Zeng Yu-Xia Sun Xiu-Hua Meng Tao Yu Hong-Tao Zhu 《Natural product research》2020,34(9):1238-1245
AbstractDasiphora fruticosa L. (Rosaceae), also known as Potentilla fruticosa L. (syn.), is a hardy deciduous shrub widely distributed in the north temperate regions of the world. Three methylene bisflavan-3-ols (1-3), together with a procyanidin dimer, (-)-afzelechin-(4α→8)-(-)-afzelechin (4) were isolated for the first time from the branches and leaves of the titled plant, in addition to 11 known compounds (5-15). Their structures were elucidated by means of extensive spectroscopic analysis and by comparison with data reported in the literatures. Methylene 6,8-bis(7-O-glucosyl) catechin (1) was determined to be a new dimeric flavan-3-ol glycoside through a methylene linkage between C-8 and C-8 of two units. At a concentration of 128?μg/mL, the known compounds 9 – 13 exhibited antibacterial activities on Escherichia coli, Staphylococcus aureus subsp. aureus, Salmonella enterica subsp. enterica, and Pseudomonas aeruginosa. Compound 12 also showed certain glucose uptake stimulating activity. 相似文献
14.
Yuan-Bin Cheng Chih-Chin Lan Wei-Chun Liu Wan-Chun Lai Yu-Chi Tsai Michael Y. Chiang Yang-Chang Wu Fang-Rong Chang 《Tetrahedron letters》2014
A chemical investigation of Zoanthus kuroshio has yielded two new alkaloids, kuroshines A (1) and B (2). The compounds possess a densely functionalized ring system on the basis of the zoanthamine frames. The structures of 1 and 2 were elucidated through interpretation of spectroscopic methods, especially 2D NMR techniques (COSY, HMQC, HMBC, and ROESY). The absolute stereochemistry of 1 was further confirmed by an X-ray single crystallographic analysis using a mirror Cu-Kα radiation. 相似文献
15.
Chemical investigations of the Australian marine sponge Ecionemia geodides resulted in the isolation of two new pyridoacridine alkaloids, ecionines A (1) and B (2), along with the previously isolated marine natural products, biemnadin (3) and meridine (4). Compounds 1 and 2 both contain an imine moiety, which is rare for the pyridoacridine structure class. The chemical structures of 1 and 2 were determined by extensive 1D and 2D NMR and MS data analyses. All compounds were tested against a panel of human bladder cancer cell lines, the increasingly metastatic TSU-Pr1 series (TSU-Pr1, TSU-Pr1-B1 and TSU-Pr1-B2) and the superficial bladder cancer cell line 5637. Ecionine A (1) displayed cytotoxicity against all cell lines, with IC50 values ranging from 3 to 7 μM. This is the first report of chemistry from the sponge genus Ecionemia. 相似文献
16.
Two new phlegmarane-type alkaloids, cermizines A (1) and B (2), three new quinolizidine alkaloids, cermizine C (3) and senepodines G (4) and H (5), and a new C16N2 type alkaloid consisting of a quinolizidine and a piperidine ring, cermizine D (6), as well as two new cernuane-type alkaloids, cernuine N-oxide (7) and lycocernuine N-oxide (8), have been isolated together with cernuine (9) and lycocernuine (10) from the club moss Lycopodium cernuum and L. chinense. The relative stereochemistry of 1-4 and 6, and the absolute stereochemistry of 5, 7, and 8 were elucidated by combination of NOESY correlations, modified Mosher's method, chemical transformations, and computational methods. Cermizine D (6) might be a biosynthetic intermediate of cernuane-type alkaloids such as 7-10. 相似文献
17.
Seven new alkaloids, named as 1,9-epoxy-9a-hydroxystenine (1), tuberostemoline A (2), tuberostemoline B (3), tuberostemoninol C (4), oxotuberostemonine A (5), the mixture of bisdehydrotuberostemonine D (6), and bisdehydrotuberostemonine E (7), together with four known alkaloids neotuberostemonine (8), sessilifoline B (9), stemoxazolidinone F (10), and tuberostemoninol A (11), were isolated from the roots of Stemona tuberosa. The structures of 1–7 were elucidated through extensive spectroscopic analysis, and the relative configurations of 1–6 and 8 were further confirmed by X-ray crystallographic data. Compounds 8, 9 and the mixture of 6 & 7 exhibited potential acetylcholinesterase (AChE) inhibitory activities. 相似文献
18.
Yukio Hitotsuyanagi Genta Shigemori Haruhiko Fukaya Maho Hikita Shu Zhu Katsuko Komatsu Koichi Takeya 《Tetrahedron letters》2013
Three new alkaloids, stemona-amines C–E, were isolated from the roots of Stemona tuberosa Lour. (Stemonaceae). The structures of stemona-amines C and D were determined by X-ray crystallography and that of stemona-amine E was determined by interpretation of spectroscopic data. The absolute structures of stemona-amines C and D were established by VCD spectroscopy. 相似文献
19.
Five new fused-hexacyclic alkaloids, daphniglaucins D (1), E (2), F (3), G (4), and H (5), and two new yuzurimine-type alkaloids, daphniglaucins J (6) and K (7), have been isolated from the leaves of Daphniphyllum glaucescens, and the structures and relative stereochemistry were elucidated on the basis of spectroscopic data and chemical means. 相似文献
20.
Yukio Hitotsuyanagi 《Tetrahedron》2007,63(4):1008-1013
Four new alkaloids, sessilifoliamides E, F, G, and H were isolated from the roots of Stemona sessilifolia (Miq.) Miq., together with a known alkaloid, tuberostemonone. The structures of new alkaloids were elucidated by interpretation of the spectral data and X-ray crystallography. 相似文献