西红花有效成分合成研究进展

西红花主要有效成分为西红花酸和西红花糖苷,论文综述西红花酸和西红花糖苷生物合成和化学合成方法.在生物合成中最关键的是用葡萄糖糖基转移酶作催化剂将西红花酸转化为西红花糖苷;共轭多烯链化合物是合成西红花有效成分的起始物,在论文中概述了几种通过Wittig和Wittig-Horner 反应合成共轭多烯链化合物的路线.     

保幼激素类似物11-甲氧基-3,7,11-三甲基-2,4-十二碳二烯酸异丙酯的简便全合成

从价廉的丙酮出发,首先经羟醛缩合、脱水、氧化、酯化、溴代反应合成了4-溴-3-甲基-2-丁烯酸异丙酯,继而与亚磷酸三乙酯反应得到了Wittig-Homer试剂,随后与香茅醛发生Wittig-Horner反应,最后在阳离子树脂催化作用下与甲醇醚化,成功地全合成了具有保幼激素活性的昆虫生长调节剂11-甲氧基-3,7,11-三甲基-2,4-十二碳二烯酸异丙酯.所得标题化合物的四种异构体中,具有较高生物活性的(2E,4E)-异构体的含量达66%.各步所合成化合物的结构经1H NMR,IR,MS分析确证.     

2-(取代哌嗪-1-甲基)-3-喹啉甲酸乙酯及其衍生物的合成、 表征及晶体结构

以邻硝基苯甲醛为起始原料, 经还原、Friedländer 缩合反应合成2-甲基-3-喹啉甲酸乙酯(2), 2经N-溴代丁二酰亚胺(NBS)溴代得到化合物3, 3再与N-取代哌嗪5a～5p 发生SN2亲核取代反应, 合成一系列2-(取代哌嗪-1-甲基)-3-喹啉甲酸乙酯及其衍生物6a～6p. 它们的结构通过元素分析, IR, 1H NMR, 13C NMR和MS进行了鉴定和表征, 并用X射线衍射法测定了化合物6n的晶体结构.     

新型D-π-A结构茋类衍生物的合成及其光学性质

以对硝基甲苯为起始原料,与NBS经溴代反应制得对溴甲基硝基苯(2);2与亚磷酸三乙酯经取代反应得4-硝基苯基膦酸二乙酯(3);4-醛基苯基亚氨基二乙酸二乙酯与3或对硝基苯乙腈分别经Wittig-Horner反应和Knoevenagel缩合反应合成了两种新型茋类化合物(5和7),其结构经1H NMR,13C NMR,IR和ESI-MS表征。用UV-Vis和荧光光谱研究了5和7的光学性质。结果表明:5和7的最大吸收峰均位于410 nm;5的荧光发射峰位于529 nm,较7红移26 nm,发射强度提高129倍。     

二硝基苯乙基氟代膦酸二乙酯的制备

在室温下,二氟溴甲基膦酸二乙酯与锌粉反应生成锌试剂;2,4-二硝基氯化苄与合成的锌试剂在溴化亚铜催化作用下即可反应生成二硝基苯乙基(氟代)磷酸二乙酯化合物。两步反应都可在室温下进行,操作简单易行。     

藏红花酸二醛的合成研究（英文）

本文提供了一种简单方便的合成2,6,11,15-四甲基-2,4,6,8,10,12,14-十六碳七烯二醛(藏红花酸二醛)的方法,即通过2,7-二甲基-2,4,6-辛三烯二醛与3-(5,5-二甲基-1,3-二恶烷-2-基)丁-2-烯基膦酸二乙酯或(3-甲基-4-氧代-2-丁烯-1-基)膦酸二乙酯进行霍纳尔-沃兹沃思-埃蒙斯(HWE)反应,以四氢呋喃为溶剂,氢化钠或叔丁醇钾为碱来合成藏红花酸二醛。所得到的化合物经过红外,核磁共振氢谱,碳谱以及质谱确认。     

(E)-脱氢二聚白藜芦醇-11,11′,13,13′-四甲醚的全合成

以3,5-二甲氧基苯甲酸(1)为起始原料, 经过甲醇酯化、氢化铝锂还原、四溴化碳溴代和Wittig-Horner反应,高产率的合成了Wittig-Horner试剂(5). 化合物5与对羟基苯甲醛(6)的羟基保护产物(7)偶联得到化合物(8),后者经去甲氧基亚甲基保护和仿生氧化偶联反应成功地全合成了(E)-脱氢二聚白藜芦醇-11,11′,13,13′-四甲醚(10). 通过1H NMR、13C NMR、IR、HRMS等测试技术确定化合物10为二聚芪类化合物(E)-脱氢二聚白藜芦醇-11,11′,13,13′-四甲醚,总收率48.93%.     

新法合成3-二茂铁基-2-丁烯酸乙酯

3-二茂铁基-2-丁烯酸乙酯是合成其他重要的二茂铁衍生物的起始原料,它本身也具有很多特殊性质。文献报道该化合物的合成方法是将乙酰基二茂铁与溴     

“一锅法”合成(E)-2-苯乙烯基喹啉-3,4-二酸二乙酯类衍生物（英文）

本文设计以2-溴甲基喹啉-3,4-二甲酸二乙酯为起始化合物,经一锅连续的Arbuzov反应/Horner-Wadsworth-Emmons(HWE)反应过程,简便而有效地合成了一系列结构新颖的(E)-2-苯乙烯基喹啉-3,4-二羧酸二乙酯类衍生物(3a～3i),其结构均已通过波谱数据和元素分析得以证实。     

2-(3-甲氧基丙基)-琥珀酸二乙酯的合成

以1,3-丙二醇为起始原料,经羟甲基化、溴代和硝化反应制得1-甲氧基-3-硝基丙烷(4);4与马来酸二乙酯的缩和产物通过钯炭催化氢化合成了新化合物2-(3-甲氧基丙基)-琥珀酸二乙酯,产率90%,其结构经1H NMR和HR-MS表征.     

Evaluation of gardenia yellow using crocetin from alkaline hydrolysis based on ultra high performance liquid chromatography and high‐speed countercurrent chromatography

Gardenia yellow is globally the most valuable spice and food color. It is generally a mixture of water‐soluble carotenoid glycosyl esters which consist of crocetin bis(gentiobiosyl) ester as the main component. Crocetin is a natural carotenoid dicarboxylic acid that may be a candidate drug for pharmaceutical development, however, it is either present in trace amounts or is absent in natural gardenia yellow products. We here propose that crocetin produced by alkaline hydrolysis can be used to qualitatively evaluate gardenia yellow products using an ultra high performance liquid chromatographic assay. A useful and efficient isolation technique for isolating high‐purity crocetin from gardenia yellow using high‐speed countercurrent chromatography is described. High‐speed countercurrent chromatographic fractionation followed by an ultra high performance liquid chromatographic assay showed that trans‐crocetin is easily converted to about 15% cis‐crocetin (85% trans‐crocetin). Crocetin in gardenia yellow was quantitatively evaluated. Our approach is based on the hydrolysis process for converting crocetin glycosyl esters to crocetin before evaluation and isolation using the ultra high performance liquid chromatographic and high‐speed countercurrent chromatographic methods. The combination of hydrolysis and chromatographic methods allows evaluation of the purity and quantity of crocetin in gardenia yellow.     

Induced chirality upon crocetin binding to human serum albumin: origin and nature

Binding to human serum albumin (HSA) of the natural, achiral carotenoid crocetin, having hypocholesterolemic and antitumour effects, was investigated in detail by circular dichroism (CD) and absorption spectroscopy. It has been shown that in the visible absorption region the crocetin–HSA complex exhibits a well-defined induced circular dichroic spectrum with two major bands of opposite sign, proving excitonic interaction between carotenoids bound in a left-handed chiral arrangement on the albumin molecule. In the course of CD titration experiments, palmitic acid gradually decreased the exciton band intensities indicating that crocetin and palmitic acid have common binding sites on HSA. To investigate potential sources of the intermolecular excitonic interaction, molecular modeling studies were performed fitting crocetin molecules to the long-chain fatty acid binding sites of HSA, determined recently by X-ray crystallographic measurements. The results suggest that binding of crocetin to domain III of the albumin might be responsible for the observed intermolecular exciton coupling. Crocetin binding was accompanied by a significant red shift in the visible absorption spectrum which has showed no excitonic contribution but rather indicates the higher polarizability of the protein environment.     

Neocrocin A: a novel crocetin glycoside with a unique system for binding sugars isolated from gardenia yellow

A novel crocetin glycosyl ester, neocrocin A (2), was isolated from gardenia yellow. The structure of 2 was elucidated as that of an all-trans-crocetin beta-D-gentiobiosyl beta-D-glucopyranosyl-(1-->6)-D-2-deoxy-glucopyranos-2-yl diester based on chemical and spectral data. The findings provide evidence that the binding system of crocetin glycosides is not limited to the anomeric position.     

西红花酸二甲酯电子吸收光谱与热力学性质的理论研究

使用密度泛函理论B3LYP方法,对西红花酸二甲酯的结构、电子吸收光谱、热力学性质进行理论计算研究,并基于Tomasi的极化统一场模型(PCM)讨论溶剂效应.结果显示,溶剂对西红花酸二甲酯的前线分子轨道特征几乎无影响,溶剂作用使该分子的最大吸收波长红移约42 nm,红移程度与溶剂极性无关.西红花酸二甲酯分子的气态热力学性质与温度的关系式分别为:Cm p=189.782+0.925T,S m=457.503+1.366T,H m=1164.899+0.195T+4.671×10-4T2,Gm=1164.899-0.263T-8.989×10-4T2.298 K时,西红花酸二甲酯分子的气态标准摩尔生成焓和标准摩尔生成自由能分别为-1180.67和-733.23 kJ·mol-1.     

Crocetin Mitigates Irradiation Injury in an In Vitro Model of the Pubertal Testis: Focus on Biological Effects and Molecular Mechanisms

Infertility is a potential side effect of radiotherapy and significantly affects the quality of life for adolescent cancer survivors. Very few studies have addressed in pubertal models the mechanistic events that could be targeted to provide protection from gonadotoxicity and data on potential radioprotective treatments in this peculiar period of life are elusive. In this study, we utilized an in vitro model of the mouse pubertal testis to investigate the efficacy of crocetin to counteract ionizing radiation (IR)-induced injury and potential underlying mechanisms. Present experiments provide evidence that exposure of testis fragments from pubertal mice to 2 Gy X-rays induced extensive structural and cellular damage associated with overexpression of PARP1, PCNA, SOD2 and HuR and decreased levels of SIRT1 and catalase. A twenty-four hr exposure to 50 μM crocetin pre- and post-IR significantly reduced testis injury and modulated the response to DNA damage and oxidative stress. Nevertheless, crocetin treatment did not counteract the radiation-induced changes in the expression of SIRT1, p62 and LC3II. These results increase the knowledge of mechanisms underlying radiation damage in pubertal testis and establish the use of crocetin as a fertoprotective agent against IR deleterious effects in pubertal period.     

Isolierung und Strukturaufklärung von Neapolitanose (O-β-D-Glucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→6)]-(D-glucose), einem neuen Trisaccharid aus den Stempeln von Gartenkrokussen (Crocus neapolitanus var.)

Isolation and Structure Elucidation of Neapolitanose (O-β-D -Glucopyranosyl-(1→2)-O-[β-D -glucopyranosyl-(1→6)]-D -glucose), New Trisaccharide from the Stigmas of Garden Crocusses (Crocus neapolitanus var.) From the stigmas of Crocus neapolitanus var. ‘Blue Bird’ two new crocetin glycosyl esters were isolated. They contained a hitherto unknown trisaccharide. For the structure elucidation a homonuclear 2D-¹H-NMR-shift-correlation experiment was carried out with the peracetate of the isolated trisaccharide. This experiment revealed that the carbohydrate is O-β-D -glucopyranosyl-(1→2)-O-[β-D -glucopyranosyl-(1→6))]-D -glucose, for which we suggest the name ‘neapolitanose’. The two new C₂₀-carotenoids from Crocus neapolitanus are crocetin (β-gentiobiosyl) (β-neapolitanosyl) ester ( 4 ) and crocetin di(β-neapolitanosyl) ester ( 5 ).     

THE CHARACTERISATION OF THE TRIPLET STATE OF CROCETIN, A WATER SOLUBLE CAROTENOID, BY NANOSECOND LASER FLASH PHOTOLYSES

Abstract— The triplet state of crocetin, which is a water soluble carotenoid, has been sensitized by psoralen. The triplet extinction coefficient, ε_T (73000 dm³ mol^-1 cm^-1 at 470 nm), the triplet-triplet spectrum and the quantum yield of triplet formation, φ_T (less than 1%) are reported in aqueous solution.
In order to calculate the extinction coefficient of crocetin it was necessary to obtain ε_T for psoralen in water (10000dm³ mol^-1 cm^-1 at 450 nm). This latter value was obtained using the complete conversion technique and is reported with the triplet-triplet spectrum.     

Simultaneous quantification of five major biologically active ingredients of saffron by high-performance liquid chromatography.

A simple, sensitive and specific high-performance liquid chromatography-UV (HPLC-UV) method has been developed for the first time to simultaneously quantify the five major biologically active ingredients of saffron, namely crocin 1, crocin 2, crocin 3, crocin 4 and crocetin. Calibration curves were derived by spiking authentic compounds and internal standard, 13-cis-retinoic acid, into herbal samples prior to extraction. Extraction was conducted simply by stirring dried herb (20 mg) with 80% aqueous methanol (5 ml) at ambient temperature in the dark for 2 h. The HPLC assay was performed on a reversed-phase C18 column with linear gradient elution using methanol and 1% aqueous acetic acid. Calibrations were linear (r2 = 0.999) for all five analytes, with overall intra- and inter-day RSDs of less than 11%. The assay was successfully applied to the determination of four crocins and crocetin in three saffron samples and two Zhizi, another crocin-containing herb. Results indicate that the developed HPLC assay can be readily utilized as a quality control method for crocin-containing medicinal herbs.     

Crocetin from the tubular calyx of Nyctanthes arbor-tristis

A carotenoid aglycone Ag-NY1 was isolated from the orange coloured tubular calyx of flowers of Nyctanthes arbor-tristis. The elucidation of the structure through a detailed spectroscopic study revealed that the carotenoid molecule is crocetin, which is the major aglycone present in the stigma of Crocus sativus. The compound exhibited a good membrane stabilising activity as compared to the corresponding glycoside crocin.