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利用易得的光学纯N-甲基氨基醇与1,2-双(二氯磷)乙烷缩合合成了一类新的具有C2对称轴的氮磷-氧磷配体(R,R)-双噁唑啉磷乙烷(BOAPE) 1~4. 该类配体不仅具有C2对称结构和刚性五元环, 还具有富电子特性, 利用500 MHz进行了1H NMR, 31P NMR, 13C NMR表征. 与这些配体配位形成的Rh配合物用于N-苯甲酰基脱氢丙氨酸衍生物和α-功能化酮不对称加氢, 分别可以得到99%和98%的ee. 这类配体比它们相对应的非C2对称的氮磷-氧磷化合物(AMPP)配体具有更高的对映选择性. 在这四个新的配体中配体(R,R)-Ph-BOAPE (2)的催化性能最优. 催化剂[Rh(COD)(R,R)-Ph-BOAPE]BF4的半反应周期t1/2和周转频率(TOF)在N-苯甲酰基肉桂酸甲酯的不对称加氢反应中分别为12 min和6.5 min-1. 相似文献
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以(S)-2-氨基丙醇为手性源与α-溴-3-氯苯丙酮反应, (R)-2-氨基丙醇为手性源与6-甲氧基-2-(2-溴丙酰基)萘反应, 分别合成了手性纯化合物(2R,3R,5S)-3,5-二甲基-2-(3-氯苯基)-2-吗啉醇盐酸盐(4a)和(2S,3S,5R)-3,5-二甲基-2-(6-甲氧基-2-萘基)-2-吗啉醇盐酸盐(4b), 利用X射线单晶衍射仪测定了两化合物的晶体结构和两化合物的空间结构, 并初步分析两化合物空间结构, 化合物4a晶体属正交晶系, 空间群为P21212, 晶胞参数为: a=0.8718(2) nm, b=0.7883(2) nm, c=2.0247(6) nm, Z=4, V=1.3915(7) nm3, Dc=1.328 g/cm3, F(000)=584, R1=0.0399, wR2=0.0797, S=1.042. 化合物4b晶体属正交晶系, 空间群为P212121, 晶胞参数为: a=0.71035 (9) nm, b=0.77703(10) nm, c=2.9820(4) nm, Z=4, V=1.6318(4) nm3, Dc=1.318 g/cm3, F(000)=688, R1=0.0520, wR2=0.1108, S=0.994. 相似文献
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合欢皮中两个新八糖苷的分离鉴定和活性研究 总被引:2,自引:0,他引:2
从合欢皮95%乙醇提取物中分离得到2个新的八糖苷(1, 2), 经化学方法与光谱分析将其结构鉴定为3-O-[β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-吡喃葡萄糖基]-21-O-[(6S)-2-反式-2-羟甲基-6-甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基]-金合欢酸-28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-
(1→2)-β-D-吡喃葡萄糖基酯(1)和3-O-[β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-2-去氧-2-乙酰氨基吡喃葡萄糖基]-21-O-[(6S)-2-反式-2-羟甲基-6-甲基-6-O-β-D-吡喃鸡纳糖基-2,7-辛二烯酸基]-金合欢酸-28-O-β-D-吡喃葡萄糖基-(1→3)-[α-L-呋喃阿拉伯糖基-(1→4)]-α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃葡萄糖基酯(2), 分别命名为合欢皂苷J25 (1, Julibroside J25)和合欢皂苷J22 (2, Julibroside J22). 1和2在体外对4种人癌细胞增殖有明显的抑制作用. 相似文献
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首次利用薯蓣皂甙元的完整骨架经16步反应以7.6%的总收率合成了骨化三醇(1α,25-二羟基维生素D3)的光化反应前体. 3-苄基保护的薯蓣皂甙元经还原开E/F环产生3,16,26-胆甾三醇-3-苄醚(5). 除去化合物5 C-16羟基后, 其C-26羟基经消除和羟基化反应转移到C-25位. 目标分子A/B环结构单元通过薯蓣皂甙元A/B环的官能团转化被构筑. 按照已知的光化反应, (1S,3R)-胆甾-5,7-二烯-1,3,25-三醇能被转化成为1α,25-二羟基维生素D3. 相似文献
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(S)-和(R)-普萘洛尔的不对称合成 总被引:3,自引:0,他引:3
普萘洛尔是一种临床上广泛使用的β受体阻断剂, 介绍了一种不对称合成(S)-和(R)-普萘洛尔的方法. 以手性Salen-CoIII催化剂水解动力学拆分外消旋环氧氯丙烷得到高光学纯度的(S)-环氧氯丙烷和(R)-3-氯-1,2-丙二醇, 以(S)-环氧氯丙烷为手性原料先水解得(S)-3-氯-1,2-丙二醇, 其与1-萘酚反应得(S)-3-(1-萘基)-丙烷-1,2-二醇, 再与氯化亚砜反应得环状亚硫酸酯, 最后和异丙胺作用得(S)-普萘洛尔, 总收率80.9%, 光学纯度大于99%; 而同样以(S)-环氧氯丙烷为手性原料直接与1-萘酚反应得(2R)-3-(1-萘氧基)-1,2-环氧丙烷, 再与异丙胺作用得(R)-普萘洛尔, 总收率74.5%, 光学纯度大于99%. 相似文献
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Two new C(19)-diterpenoid alkaloids, piepunensine A (1) and 18-acetylcammaconine (2), have been isolated from the roots of Aconitum piepunense together with five known alkaloids pengshenine B (3), talatisamine (4), aconosine (5), yunaconitine (6), and talatizidine (7). The structures of the new alkaloids were established on the basis of spectral data (1D- and 2D-NMR, HR-MS). 相似文献
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Two manzamine-class alkaloids, manzamine A (1) and 8-hydroxymanzamine (2) were isolated from a Japanese marine sponge Acanthostrongylophora aff. ingens, together with three known alkaloids manzamine E (3), manzamine F (4), and manzamine X (5). The spectral features of 1 and 2 were different from the reported data. Detailed structure analysis using 2D NMR revealed the structure of 1 and 2 as a free base form of hydrochloric salt. These manzamine-class alkaloids showed neuritogenic activity against Neuro 2a cells. 相似文献
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Four new and five known norditerpenoid alkaloids were isolated from the processed tubers of Aconitum carmichaeli. The new alkaloids are 14-O-cinnamoylneoline (3), 14-O-anisoylneoline (4) 14-O-veratroylneoline (5), and lipo-14-O-anisoylbikhaconine (8). The known alkaloids are neoline (1), 14-O-acetylneoline (2), foresaconitine (6), crassicauline A (7), and lipohypaconitine (9). Alkaloids 2, 6, and 7 were isolated from this plant for the first time. The structures of the new alkaloids were established by spectroscopic and chemical methods. 相似文献
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Two new bisbenzylisoquinoline alkaloids, alpha, alpha'-dioxo-7'-O-demethylstebisimine (1) and 7'-O-demethylstebisimine (2), along with 14 known alkaloids, were isolated from the roots of Cocculus laurifolius. These alkaloids were characterized mainly by spectroscopic methods. 相似文献
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<正>Three new sesquiterpene alkaloids,1-desacetylwilforgine(1),1-desacetylwilforine(2),and 9′-hydroxy-2-nicotinoylwilforine (3) were isolated from the roots of Tripterygium wilfordii Hook f.,along with six known alkaloids.Their structures were established on the basis of spectral analysis. 相似文献
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In this study, seven alkaloids were detected in Wu-tou decoction using ultra performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MSn). The aim of this study was to investigate the effect of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, Pinelliae Rhizoma in different ratios with Wu-tou decoction (2:1, 1:1, 1:2) by measuring the therapeutic effects in Wu-tou decoction of main seven alkaloids including benzoylaconitine (BA), benzoylmesaconitine (BM), benzoylhypaconitine (BH), hypaconitine (HA), fuziline (FU), niaolin (NE) and deoxyaconitine (DA). The permeability of aconitum alkaloids extract through a Caco-2 cell monolayer was analyzed in the absence and presence of Fritillariae Cirrhosae Bulbus, Fritillariae Thunbergii Bulbus, and Pinelliae Rhizoma, respectively. The results showed that Pinelliae Rhizoma could reduce the absorption of the alkaloids and increase the excretion of the alkaloids, which would attenuate the therapeutic effects of Wu-tou decoction. Therefore, Pinelliae Rhizoma is an incompatible herb of Wu-tou decoction because of the inhibition of the absorption of alkaloids in the intestine. And that Fritillariae Cirrhosae Bulbus and Fritillariae Thunbergii Bulbus showed the effects to improve the permeability of the alkaloids in Wu-tou decoction. These effects of these two herbs were similar, but the former was stronger than the latter, which most likely is due to the fact that the compositions of these two traditional Chinese medicines are similar. The in vitro data suggests that the compounds such as fritillary presented in alkaloids in the formula maybe improve the therapeutic function caused by the increased bioavailability of alkaloids in intestine. 相似文献
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Jitsuno M Yokosuka A Hashimoto K Amano O Sakagami H Mimaki Y 《Natural product communications》2011,6(2):187-192
An alcoholic extract of Lycoris albiflora (Amaryllidaceae) showed potent cytotoxic activity against HL-60 cells with an IC50 value of 1.7 microg/mL. Phytochemical examination of the extract resulted in the isolation of 15 alkaloids, including two phenanthridine-type alkaloids (1, 2), one benzylphenethylamine-type alkaloid (3), two crinane-type alkaloids (4, 5), one pyrrolophenanthridine-type alkaloid (6), six lycorenan-type alkaloids (7-12), and three galanthamine-type alkaloids (13-15), together with three neolignans (16-18), two flavans (19, 20), and two acetophenone derivatives (21, 22). Compound 3 (hostasinine A) has not been isolated from Amaryllidaceae plants, and 1, 2, 4, 5, 7-9, 11, 12 and 14-22 are the first isolation and identification from L. albiflora. The phenanthridine-type alkaloids (1, 2), as well as the alkaloids (3-5), exhibited potent cytotoxic activities against not only HL-60 cells but also HSC-2 cells, thus leading to the conclusion that these alkaloids are mainly responsible for the cytotoxicity of the L. albiflora extract. Compound 1 (lycoricidinol), with the most potent cytotoxic activities, induced apoptosis in both HL-60 cells and HSC-2 cells. It is notable that 1 induced transient autophagy and morphological changes in mitochondria in the early stages of the apoptotic cell death process in HSC-2 cells. 相似文献
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应用多种色谱和波谱学方法,从云南蕊木(Kopsia officinalis)茎中分离鉴定了27个单萜吲哚生物碱,包括7个新化合物kopsiofficines A~G和20个已知化合物.此外,建立脂多糖(LPS)诱导的小鼠巨噬细胞RAW 264.7炎症模型,通过测定IL-1β, PGE2和TNF-α炎症因子释放评价生物碱的抗炎活性.结果表明, kopsiofficines A (1), kopsiofficines B (2),kopsiofficines D(4),kopsiofficines F(6),kopsiofficines G(7), 12-methoxykopsine(11),kopsinoline(15),(-)-N-methoxy-carbonyl-11,12-methylenedioxykopsinaline(16),kopsinine(18)和kopsinic acid(20)表现出显著的抗炎活性,与阳性对照(地塞米松)基本相当.研究发现C-5位丙酮基取代的单萜吲哚生物碱的抗炎活性明显强于原型生物碱,推测丙酮基可能是抗炎活性的药效促进基团,研究结果为进一步的结构修饰... 相似文献
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Yun YS Sugimoto N Sekita S Maitani T Yamada T Satake M 《Chemical & pharmaceutical bulletin》2000,48(12):1990-1991
Chemical constituents of MeOH extracts of cigarette smoke were studied. Two new alkaloids, named cigatin A (1), 2-(Pyridine-3-yloxy)-benzene-1',4'-diol and B (2), 2-(4-Methyl-pyridin-3-yloxy)-benzene-1',4'-diol, were isolated from a mainstream condensate of cigarette together with seven known alkaloids. Their structures were determined on the basis of spectral data and chemical methods. 相似文献
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NMR spectral assignments of three aspidofractinine alkaloids, kopsine, fruticosine and fruticosamine
1D and 2D NMR techniques were used to assign fully the spectra of three aspidofractinine alkaloids, kopsine (1), fruticosamine (2) and fruticosine (3), isolated from a cultivated specimen of the plant Kopsia fruticosa (Apocynaceae). The assignment of the NMR data for 1, 2 and 3 will help in the future assignments of related alkaloids. 相似文献