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1.
焦晓臻  姜英俊  谢平  梁晓天 《有机化学》2007,27(12):1537-1541
以4-戊烯酸及(R)-4-苯基-2-噁唑烷酮为起始原料, 以氯化镁在三乙胺和三甲基氯化硅存在下催化的(R)-4-苯基-3-戊烯酰基-2-噁唑烷酮的埃文斯(Evans)反式羟醛缩合反应为关键步骤, 经9步反应合成了(-)-7(R)-羟罗汉脂素, 其光谱数据与文献报道的天然产物一致.  相似文献   

2.
程青芳  王启发  许兴友  叶燕斌  张辉 《有机化学》2007,27(12):1558-1561
研究了一种化学不对称合成盐酸(R)-沙丁胺醇的方法. 以自制的手性龙脑基β-二酮铁络合物为催化剂催化起始原料3-乙酰氧基甲基-4-乙酰氧基苯乙烯(1)的不对称环氧化, 得到(R)-3-乙酰氧基甲基-4-乙酰氧基苯基环氧乙烷(2), 这一步的化学收率和光学收率都较高. 然后环氧化合物2与叔丁胺发生开环反应, 再与盐酸成盐即制得盐酸(R)-沙丁胺醇. 合成盐酸(R)-沙丁胺醇只需两步, 总收率为68%. 还考察了反应温度、催化剂种类、催化剂的量等因素对3-乙酰氧基甲基-4-乙酰氧基苯乙烯(1)的不对称环氧化的化学产率和光学收率的影响.  相似文献   

3.
以薯蓣皂素为原料, 经过磺酰酯化、N-溴代丁二酰亚胺(NBS)氧化加成、Pb(OAc)4远程氧化关环、消去反应、间氯过氧苯甲酸(mCPBA)氧化、高氯酸开环及锌粉还原7步反应, 合成多羟基甾体25(R)-异螺甾环-5-烯-2β,3α,19-三醇. 并用IR, 1H NMR, 13C NMR, MS及元素分析对各中间体及目标化合物进行了表征.  相似文献   

4.
李涛  黄贤贵  林静容  金荣华  田伟生 《化学学报》2007,65(12):1165-1171
(2R,6R)-2,6,10-三甲基十一醇(1)是维生素E、维生素K和植醇的基本结构单元. 利用从甾体皂甙元氧化降解产生的工业废弃物中所获得的手性化合物(R)-5-甲基-δ-戊酸内酯(6), 先将其转化成为化学性质稳定的(4R)-甲基-5-甲氧甲氧基戊酸甲酯(7), 再经十二步反应, 以14.1%的总收率合成得到了目标化合物(2R,6R)-2,6,10-三甲基十一醇(1).  相似文献   

5.
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   

6.
利用2,3,3-三甲基-3H-吲哚高氯酸盐、1-苯基-3-(4-甲氧基苯基)-2-丙烯-1-酮与哌啶在微波辐射条件下合成了9,9-二甲基-2-(4-甲氧基苯基)-4-苯基-9H-吡啶并[1,2-a]吲哚高氯酸盐, 在甲醇中培养出单晶, 通过X射线单晶结构分析法测定分子结构和晶体结构, 晶体属于正交晶系, Pca21空间群, 晶胞参数为: a=2.7923(6) nm, b=0.92126(17) nm, c=1.8345(4) nm, V=4.7190(16) nm3, Dc=1.345 g/cm3, μ=0.201 mm-1, F(000)=2000, Z=8, R1=0.0566, wR2=0.1320.  相似文献   

7.
陶明  陈丽  熊伟  袁茂林  陈华  李贤均 《有机化学》2006,26(4):559-562
报道了配合物RuCl2(BISBI)[(R,R)-DPEN] [BISBI=2,2'-二(二苯膦亚甲基)-1,1'-联苯, DPEN=1,2-二苯基乙二胺]的合成和表征, 并研究了其在苯乙酮不对称加氢反应中的催化性能. 考察了底物/催化剂物质的量比、碱浓度、反应温度和氢气压力等对催化活性和对映选择性的影响, 在苯乙酮/KOH/催化剂的物质的量比为30000∶250∶1, 氢气压力为2 MPa, 反应温度为35 ℃时, 苯乙酮的转化率和生成α-苯乙醇的对映选择性分别达到了100%和65% ee.  相似文献   

8.
对-二甲氨基苯甲醛和苯基氨基硫脲缩合反应生成1-[4-(二甲氨基)苯亚甲基氨基]-4-苯基硫脲(DMB), 产物能从溶液中析出单一手性对映体晶体. 用单晶X射线衍射技术测定了它的绝对构型, 晶体属正交晶系, P212121空间群, a=0.7870(2) nm, b=1.1560(2) nm, c=1.6668(3) nm, V=1.5164(5) nm3, Z=4, Dc=1.307 g/cm3, F(000)=632, μ=0.213 mm-1, 2557个可观测点[I>2s(I)]精修的最终残差因子: R=0.0409, wR=0.1061, Flack参数为0.00(9), 能够确定绝对构型. 化合物的晶体结构和大宗粉末样品的固体圆二色谱表明化合物在结晶过程中发生单一对映体的手性堆积.  相似文献   

9.
4-氨基-1,2,4-三唑-5-酮(ATO)与硫氰酸钾、氯甲酸乙酯在乙酸乙酯中反应, 合成了4-(1,2,4-三唑-5-酮-4-基)-3-硫代脲酸乙酯, 在室温下采用缓慢蒸发溶剂二甲基甲酰胺得到合适的可用于X射线衍射的单晶. 晶体属六方系, 空间群为R-3, 晶体结构参数为a=2.60524(7) nm, b=2.60524(7) nm, c=0.82579(6) nm, γ=120°, V=4.8540(4) nm3, Dc=1.442 g/cm3, μ=0.300 mm-1, F(000)=2190, Z=18, R1=0.0569, wR2=0.1424. 选取标题化合物的一个结构单元作为初始模型, 运用Gaussian 03程序对化合物进行了HF/6-311G, MP2/6-311G和B3LYP/6-311G水平的几何全优化,并对其原子电荷及自然键轨道(NBO)进行了分析.  相似文献   

10.
肖元晶  杨守宁  石炜  杨琍苹 《有机化学》2006,26(8):1103-1105
用手性(S,S)-Ru-TsDPEN催化剂不对称转移氢化α-亚胺酮化合物5-[(1,1-二甲基乙基)亚胺基]乙酰基-2-羟基苯甲酸甲酯(2)得光学纯β-氨基芳基乙醇类化合物(R)-5-[2-[(1,1-二甲基乙基)氨基]-1-羟乙基]-2-羟基苯甲酸甲酯(3), 再经一步还原反应即得(R)-(-)-沙丁胺醇. 对反应关键一步α-亚胺酮的不对称转移氢化反应条件进行了研究.  相似文献   

11.
标题化合物C23H22BrNO是由1-(4-溴苯基)-3-苯基-2-丙烯-1-酮与5,5-二甲基-1, 3-环己二酮在N, N-二甲基甲酰胺(DMF)中在NH4OAc催化下反应而得。结构通过单晶X-射线衍射分析确定,其晶体属于单斜晶系,空间群C2/C, a = 19.678(4),b = 13.571(2),c = 17.311(3) 牛琤 = 118.74(1),Mr = 408.33, V = 4055(1) ?,Dc = 1.338 g/cm3, Z = 8, m (MoKa) = 2.038 mm-1, F(000) = 1680, R = 0.0539,wR = 0.1369。X-衍射分析表明,六元环C(10)C(13)C(16)C(17)采用半椅式构象:原子C(10),C(11),C(12),C(16)和C(17)在同一个平面内,而原子C(13)远离平面为0.3282 牛闷矫嬗?个苯环的夹角分别为41.09, 81.97,2个苯环的夹角为75.87。另外在晶体结构中,存在1个分子间氢键。  相似文献   

12.
1INTRODUCTIONThepyrazolo[3,4-b]pyridineclassofcompoundspossessmanybiologicalandpharmacologicalactivi-ties[1],suchasactiveanti-concretionmedicaments[2]aswellasactiveanti-gramnegativeandpositivebacteriaagents[3].Thereforethesynthesesofsuchcompoundshavearousedgreatattentionofalargenumberofchemists.Themostimportantsyntheticrouteisthecondensationreaction[4~11]ofamino-pyrazoleandα,β-unsaturatedcompounds.Theorganicreactionundermicrowaveirradia-tionhastheadvantagesoffastreactionspeed,shorttime…  相似文献   

13.
5-Amino-3-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-7-phenyl-7H-thiazolo[3,2-a]pyrimidine-6-carbonitrile was synthesized via the reaction of 4-(2-aminothiazol-4-yl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidene malononitrile and was then transformed to related fused heterocyclic systems. The antifungal and antibacterial studies revealed in some cases excellent biocidal properties.  相似文献   

14.
Optically pure (5R)- [and (5S)]-5,6-dihydro-5-phenyl-2H-1, 4-oxazin-2-one N-oxides [(5R)- and (5S)-2] were designed as chiral (E)-geometry-fixed alpha-alkoxycarbonylnitrones 1. The nitrones (5R)- and (5S)-2 were synthesized by three-step oxidation of (R)- and (S)-phenylglycinols [(R)- and (S)-3], condensation of the resulting (R)- and (S)-2-hydroxylamino-2-phenylethanols [(R)- and (S)-5] with glyoxylic acid, and cyclization of the intermediary nitrones (R)- and (S)-6b. The nitrone (5R)-2reacted with olefins 7-14 under mild conditions to afford the corresponding cycloadducts 15-22 as the main products via the least sterically demanding exo modes. Cycloadduct 30 obtained from (5S)-2 and cyclopentadiene was effectively elaborated to (1S,4S, 5R)-4-benzyloxycarbonylamino-2-oxabicyclo[3.3.0]oct-7-en-3-one (28), the key synthetic intermediate of carbocyclic polyoxin C.  相似文献   

15.
The reaction of 6-(tert-butyl)-3-hydrazino-1,2,4-triazin-5(2H)-one with acetone and benzaldehyde yields the corresponding hydrazones. In the presence of thionyl chloride the benzaldehyde hydrazone is converted to 3-(tert-butyl)-6-phenyl-1,2,4-triazolo[4,3-b]-1,2,4-triazin-2(1H)-one and this can also be formed via the acylation of the starting hydrazinotriazinone using benzoyl chloride.  相似文献   

16.
Fostriecin(CI-920) 11 a potential anticancer agent presently in phase I clinical trials at NCI is a novel phosphate ester produced by Streptomyces pulveraceus. Scheme 1 1 2 3 5 4 Synthesis of C10 epimer of compound 1 had been reported by Just G2. during the determination of its structure. On the basis of Just’s synthesis, a revised retro-asymmetric synthetic route of Fostriecin (scheme 1) was designed here of which compound 3 was synthesized from 5 with C3 in R configuration correspondi…  相似文献   

17.
 将水溶性手性二胺 (S,S)-1,2-二苯基乙二胺二磺酸钠 ((S,S)-DPENDS) 与钌膦配合物 ([RuCl2(TPPTS)2]2) 原位生成的催化剂用于催化水相中苄叉丙酮的不对称加氢反应. 在优化条件下, 羰基加氢产物 4-苯基-3-丁烯-2-醇的选择性可达 96.0%, 对映选择性可达 71.2%. 经正己烷简单萃取后即可实现催化剂与加氢产物的分离, 循环使用 5 次后, 目标产物 4-苯基-3-丁烯-2-醇选择性和对映选择性没有明显下降.  相似文献   

18.
3-Hydroxy-3-(2-oxoethyl)-6-phenyl-2,3-dihydropyridazin-4(1H)-ones were obtained by the reaction of methyl 3-oxo-5-phenylfuran-2(3H)-ylideneacetate or 2-[2-(4-chlorophenyl)-2-oxoethylidene]-5-phenylfuran-3(2H)-one with benzoic or p-nitrobenzoic isopropylidenehydrazides. Equilibrium C(5)H and C(5)H2 tautomeric forms were detected in solutions of the 4-chlorophenyl derivatives in DMSO-d6. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1156–1158, August, 2007.  相似文献   

19.
CX-659S (1) [(S)-6-amino-5-(6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxamido)-3-methyl-1-phenyl-2,4-(1H,3H)-pyrimidinedione], has been developed as a new type anti-inflammatory agent for the treatment of dermatitis. The structure of a major metabolite of CX-659S was determined as (S)-6-amino-5-[2-hydroxy-2-methyl-4-(2,4,5-trimethyl-3,6-dioxo-1,4-cyclohexadienyl)butanamide]-3-methyl-1-phenyl-2,4-(1H,3H)-pyrimidinedione (2) by direct comparison with the synthesized authentic compound. The anti-inflammatory activity of 2 was equipotent with that of 1 on the contact hypersensitivity reaction (CHR) induced by picryl chloride (PC) in mice, suggesting that compound 2 contributes, at least in part, to the anti-inflammatory activity of CX-659S.  相似文献   

20.
The reaction of 2-phenyl-5-(4H)-oxazolone 1 and its 4-benzylidene derivative 2 with oxovinylidenetriphenylphosphorane 3 afforded 2-phenylfuro [3,2-d] [1,3]oxazol-5-(6H)-one 6 and 2,7-diphenyl-5H-pyrano[3,2-d][1,3]oxazol-5-one 7 along with triphenylphosphine. Alternatively, when 2-phenyl-5-(4H)-oxazolone 1 reacts with phosphorus ylides 4a–f the corresponding new phosphorane, the cyclic and/or the olefinic adducts were obtained. Moreover, oxazolone reacts with N-(triphenylphosphoranylidene)aniline 5 to give the new imino product 14 together with triphenylphosphine oxide. Possible reaction mechanisms are considered and the structural assignments are based on analytical and spectroscopic results. Biological evaluations of the new products are also studied.  相似文献   

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