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通过异亚丙基和苄基的选择性保护和脱保护法,分别方便地合成了6位带有自由羟基的半乳糖和葡萄糖,并进一步选择性地对其进行6位苯甲酰基化修饰从而获得相应糖给体。从6位苯甲酰基化半乳糖和葡萄糖糖给体出发,立体专一性地合成了β-构型的芳香碳糖苷中间体,再经硝酸铈铵(CAN)温和氧化烷氧基苯获得6-O-苯甲酰基苯醌碳糖苷目标化合物,其中4个结构未见文献报道。经1HNMR、13CNMR谱及高分辨质谱测试技术分析确证了目标化合物结构。采用MTT法考察了目标化合物对黑色素肿瘤细胞株A375的体外抑制活性。结果表明,2-(2,3,4-三-O-乙酰基-6-O-苯甲酰基-β-D-吡喃半乳糖)-1,4-苯醌(6)和2-(2,3,4-三-O-乙酰基-6-O-苯甲酰基-β-D-吡喃葡萄糖)-1,4-苯醌(15)显示体外抗肿瘤活性。对此类化合物进一步的结构优化,开发高选择性、高活性的抗肿瘤先导化合物提供了信息。 相似文献
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HPLC法测定油茶枯饼中两种主要黄酮苷 总被引:2,自引:0,他引:2
建立了油茶枯饼中两种主要黄酮苷:山奈酚3-0-[2-O-β-D-木糖-6-0-α-L-鼠李糖]-β-D-葡萄糖苷(Ⅰ)和山奈酚3-0-[2-O-β-D-半乳糖-6-0-α-L-鼠李糖]-β-D-葡萄糖苷(Ⅱ)的高效液相色谱测定方法。采用C18 Column(BDS,Hypersil,250mm×4.6 mm),流动相为V(乙腈)∶V(0.1%H3PO4)=20∶80,流速1 mL/min;检测波长266 nm。结果表明,黄酮苷Ⅰ的线性范围为60-2000 mg/L(R=0.9993,n=6),平均回收率99.5%,RSD为1.6%;黄酮苷Ⅱ的线性范围为30-1200mg/L(R=0.9995,n=6),平均回收率100.7%,RSD为1.2%。该方法可用于检测油茶枯饼及其提取物中两种主要黄酮苷。 相似文献
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《有机化学》2020,(6)
以2,3,4-三-O-苯甲酰基-α-L-鼠李糖三氯乙酰亚胺酯、2,4-二-O-苯甲酰基-α-L-鼠李糖对甲氧基苯基苷、2,3,4,6-四-O-苯甲酰基-β-D-葡萄糖三氯乙酰亚胺酯和2,3-O-异丙叉基-α-L-鼠李糖对甲氧基苯基苷为原料,采用[2+2]偶联策略,对巴西固氮螺菌(Azospirillum brasilense type strain Sp246)表面脂多糖的四糖重复单元α-L-鼠李糖-(1→3)-α-L-鼠李糖-(1→3)-[β-D-葡萄糖-(1→4)]-α-L-鼠李糖结构进行全合成.在合成单元子的反应中,采用硅胶负载高氯酸(HClO_4-SiO_2)作为酸性催化剂,三乙基硅基作为选择性保护基,简单高效地构建全保护的四糖.该合成路线步骤短,试剂种类少,反应后处理简单,以L-鼠李糖为原料计算,目标化合物四糖总收率达到23%,化合物结构经~1H NMR和~(13)C NMR、HRMS和IR确证. 相似文献
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杨梅素是一种主要用于抗炎的多酚类黄酮化合物,为改善其水溶性和稳定性,合成了杨梅素-3-O-β-D-乳糖,并开发了一条高效的合成路线。首先以杨梅苷为起始原料,对杨梅苷的5位、7位、3′位、4′位和5′位酚羟基进行保护,形成五苄基保护的杨梅苷。然后脱除3位鼠李糖,再与乙酰基保护的乳糖溴苷反应,最后通过依次脱去乙酰基和苄基得到目标化合物。经过路径优化,最终以更高效的方法合成了杨梅素-3-O-β-D-乳糖,减少了副产物的生成,提高了原合成路线总收率,此方法的总产率为44.5%。该路径得到了2个新型的杨梅素衍生物中间体。目标化合物的结构均经过1H NMR,13C NMR和HR-MS(ESI)确证。 相似文献
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苯丙素苷是从药用植物中提取出的具有取代苯乙基和取代肉桂酰基的一系列天然糖苷化合物的统称,其糖核一般由一到四个单糖构成.许多研究表明,这类化合物具有抗菌、抗病毒、抗肿瘤、镇痛、降压、治疗糖尿病和免疫调节等明显的生物活性[1],因此它们的合成研究已得到有机合成化学家的注意[2].二糖苯丙素苷Lugrandoside是从毛地黄属药用植物中分离出来的一种天然化合物[3],具有强的抗氧化活性[4].本文从D-葡萄糖出发,经过15步反应,得到了全保护的二糖(3,4-二-O-烯丙基)-β-苯乙基(2,3,4,6-四-O-乙酰基)-O-β-D-吡喃葡萄糖基(1→6)-4-O-(3,4-二-O-烯丙基)咖啡酰基-2,3-二-O-乙酰基-1-O-β-D-吡喃葡萄糖,脱去保护基团,最终合成出Lugrandoside的研究正在进行之中. 相似文献
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The pseudolactones 6 and 12 were prepared in a straightforward way from methyl α-D -glucopyranoside and methyl α-D -mannopyranoside, respectively. The pseudolactone 6 reacted with tert-butyl lithioacetate to give the protected, trihydroxylated cyclohexenone carboxylate 7 (51 %). The sterically hindered, L-ribo-configurated pseudolactone 12 reacted with diethyl ethylphosphonate and dimethyl methylphosphonate to give the protected trihydroxycyclohexenones 17 (49 %) and 18 (62 %), respectively. The hydroxymethylated cyclohexenone 21 was obtained from 18 by treatment with Me2AlSPh and then formaldehyde, oxidation of the product 19 , and elimination. Deprotection of 21 gave 2 , identical with KD16-Ul. Esterification of 2 gave 1 , identical with the title compound. Alternatively, 1 was obtained in higher yields by esterification of 21 , followed by deprotection of the hydroxy groups. This synthesis gave 1 and 2 from methyl α-D -mannopyranoside in an overall yield of 18 and 20 %, respectively, confirming their absolute configuration. 相似文献
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克拉霉素在不同条件下水解, 分别生成3-羟基克拉霉素(2)和3-羟基-8,9,10,11-二脱水-9,12-半缩酮克拉霉素(3), 用乙酸酐保护2的C(2’)-OH得到2′-乙酰基-3-羟基克拉霉素(4), 用N-氯代琥珀酰亚胺(NCS)氧化4的C(3)—OH合成了2’-乙酰基-3-氧代克拉霉素(5), 采用MS, IR, 1H NMR, 13C NMR等对这些化合物进行了表征. 用X射线单晶衍射法测定了化合物2和5的晶体结构, 其均属于正交晶系, P212121 空间群. 化合物2的晶胞参数a=1.3657(3) nm, b=1.4783(3) nm, c=1.6510(3) nm, Z=4, V=3.3332(12) nm3, Dc=1.175 g/cm3, F(000)=1288, μ=0.087 mm-1; 化合物5的晶胞参数 a=1.5124(3) nm, b=1.5247(3) nm, c=1.5288(3) nm, Z=4, V=3.5254(12) nm3, Dc=1.187 g/cm3, F(000)=1368.0, μ=0.088 mm-1. 相似文献
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以1,5-苯并硫氮杂(1a~1o)为原料, 在三乙胺作用下与α-氯代喹喔啉-2-甲醛肟(2)发生1,3-偶极环加成反应得到一系列噁二唑并[5,4-d][1,5]苯并硫氮杂衍生物3a~3o. 产物的结构经元素分析、IR和1H NMR确认. 并用X射线衍射法测定了化合物3a的晶体结构. 化合物3a属三斜晶系, 空间群P-1, 晶胞参数: a=0.97376(19) nm, b=1.0017(2) nm, c=1.3526(3) nm, α=78.50(3)°, β=84.30(3)°, γ=68.26(3)°, Mr=486.58, V=1.2005(4) nm3, Dc=1.346 Mg/m3, Z=2, F(000)=508. 相似文献
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以(-)-葑酮为原料经中间体葑胺合成4-葑基氨基硫脲(4), 4与醛缩合得到11个未见文献报道的葑基缩氨基硫脲(5), 5用六氰合铁(III)酸钾氧化成环得到相应的2,5-二取代-1,3,4-噻二唑类化合物(6); 产物的结构经IR, NMR和元素分析确认, 并用X射线衍射法测定化合物6d的晶体结构. 化合物6d属单斜晶系, P2(1)空间群, 晶胞参数 a=1.18719(10) nm, b=1.48814(18) nm, c=1.21629(12) nm, β=118.113(2)°, Mr=343.48, V=1.8953(3) nm3, Dc=1.204 Mg/m3, Z=4, λ=0.071073 nm, μ(Mo Kα)=0.181 mm-1, F(000)=736. 相似文献
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1,3-偶极环加成合成双-1,2,4-噁二唑啉衍生物及单晶结构 总被引:1,自引:0,他引:1
2-苯基-1,2,3-三唑基-4-甲醛与1,3-丙二胺或对苯二胺缩合, 形成新的双席夫碱3和4, 然后分别与氯代肟在三乙胺条件下发生1,3-偶极环加成, 得到新型双-1,2,4-噁二唑衍生物6a~6f和7a~7f. 结构经元素分析, IR, 1H NMR和MS确证, 并用X射线衍射法测定了化合物6e的晶体结构. 化合物6e属于单斜晶系, C2/c空间群, 晶胞参数 a=3.5134(8) nm, b=0.50575(11) nm, c=2.0598(5) nm, α=90°, β=102.02(8)°, γ=90°, Mr=756.81, V=3.5798(14) nm3, Dc=1.404 g/cm3, Z=4, F(000)=1576, μ=0.095 mm-1, R=0.0787, wR=0.2093. 相似文献
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新型双席夫碱类化合物的合成及晶体结构 总被引:2,自引:0,他引:2
用2-苯基-1,2,3-三唑基-4-甲醛、喹喔啉基-2-甲醛和2-(4-溴苯基)-1,2,3-三唑基-4-甲醛为原料, 在冰醋酸的条件下分别与二胺反应, 合成了一系列新的双席夫碱5a~5d, 6a~6d和7a~7d. 目标化合物的结构经元素分析, IR, 1H NMR, MS, X射线确证. 同时测定了化合物6c的晶体结构. 其属于单斜晶系, C2/c空间群, 晶胞参数 a=1.7670(4) nm, b=0.48001(10) nm, c=1.1751(2) nm, α=90.00°, β=94.42(3)°, γ=90.00°, V=0.9937(4) nm3, Dc=1.399 g/cm3, Z=2, F(000)=436, μ=0.089 mm-1, R=0.0413, wR=0.1067. 初步生物活性筛选结果表明, 目标化合物6b在Vero细胞上有抗疱疹病毒I型活性. 相似文献
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Abstract Sequential tritylation, benzoylation and detritylation of D-glucose, followed by resolution of the crude product by chromatograpEy gave crystalline 1,2,3,4-tetra-O-benzoyl-α- (1) and β-D-glucopyranose (2). Compound 1, 2, and the corresponding methyl α-glycoside 5 were treated with dimethylaminosulfur trifluoride (methyl DAST) to give, respectively, the 6-deoxy-6-fluoro derivatives 3, 4, and 6. Crystalline 2,3,4-tri-O-benzoyl-6-deoxy-6-fluoro-α-D-glucopyranosyl chloride (10) could be obtained from either 3, 4, or 5 by reaction with dichloromethyl methyl ether in the presence of anhydrous zinc chloride. Silver trifluoromethanesulfonate-promoted reaction of 10 with methyl 2-O-(9) and 3-O-benzyl-4,6-O-benzylidene-α-D-glucopyranoside (8) gave the corresponding, (β-linked disaccharidës in high yield. Subsequent deprotection afforded the 6′-deoxy-6′-fluoro derivatives of methyl α-sophoroside (13) and methyl 6′ -deoxy-o′-fluoro-α-laminaribioside (16). Condensation of 8 and 9 with 6-O-acetyl-2,3,4-tri-O-benzyl-α-D-glucopyranosyl chloride in the presence of silver perchlorate was highly stereoselective and produced the α-linked disaccharidës 17 and 21, respectively, in excellent yield. Deacetylation of 17 and 21, followed by fluorination of the resulting alcohols 18 and 22 with methyl DAST and subsequent hydrogenolysis, gave 6′-deoxy-6′-fluoro derivatives of methyl α-kojibioside and methyl α-nigeroside 20 and 24, respectively. 相似文献
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Solutions of chloranil (CA) in chlorobenzene were irradiated in the presence of cyclobutene and cyclopropene. Cyclobutene gave rise to two conventional 1 : 2 cycloadducts onto the dichloroethene subunits of CA and an α,β-unsaturated α,γ-dichloro-γ-lactone. Heating of the crude product in methanol converted the lactone into an α,β-unsaturated methyl γ-oxocarboxylate (25% yield) and a large amount of the major 1 : 2 cycloadduct, which contains chlorocyclobutane entities, into a cyclopropylcarbinyl chloride derivative (24% yield). An entirely new product type was the result in the case of cyclopropene. After treatment of the crude product with methanol a tetracyclic acetal containing a cyclopentanone and a dihydropyran subunit was isolated in 36% yield. Apparently, CA had taken up two molecules of cyclopropene. One of the resulting cyclopropane entities must have undergone a rearrangement en route to the final product. 相似文献
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1-氨基-1-肼基-2,2-二硝基乙烯(AHDNE)的合成、 晶体结构和理论计算 总被引:7,自引:0,他引:7
利用1,1-二氨基-2,2-二硝基乙烯(FOX-7)和水合肼在水体系中合成了1-氨基-1-肼基-2,2-二硝基乙烯(AHDNE), 并在甲醇溶液中培养出可用于X射线衍射的单晶. 晶体属正交晶系, 空间群为Pnma, 晶胞参数为: a=0.6283(4) nm, b=0.7713(5) nm, c=1.2280(8) nm, a=b=g=90°, V=0.5950(7) nm3, Dc=1.821 g/cm3, μ=0.171 mm-1, F(000)=336, Z=4, R1=0.0489, wR2=0.1456. 选取标题化合物的一个结构单元作为初始模型, 运用Gaussian 03程序, 在6-311+G(d)的基组水平上, 用HF, MP2以及B3LYP三种计算方法对标题化合物进行了几何全优化, 并对其成键情况及自然键轨道(NBO)进行了分析. 相似文献
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A pair of novel chiral auxiliaries SAMIQ/RAMIQ was synthesized from l- or d-phenylalanine methyl ester hydrochloride over six steps in 45.8% and 44.4% yield, respectively. The SAMIQ-/RAMIQ-hydrazone methodology was applied for the asymmetric Michael addition of ketones to α,β-unsaturated carboxylic acid methyl esters, which afforded 3-substituted-5-oxo-alkanoates in moderate to good yield (65–82%) with excellent enantioselectivity (ee=95.3%∼>99.5%). 相似文献