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1.
An efficient synthetic route to muurolane type sesquiterpenes starting from (R)-carvone,employing allylic diazene rearrange-ment and the ring closing methesis (RCM) reaction as key steps,is described.The first asymmetric total synthesis of (-)-10α-hydroxy-4-muurolen-3-one B and (-)-10β-hydroxy-4-muurolen-3-one C was accomplished.Through the total synthesis,the absolute configurations of the natural products A,B and C were established. 相似文献
2.
Hai Qian Wen Long Huang Xiao Ming Wu Hui Bin Zhang Jin Pei Zhou Wen Cai Ye 《中国化学快报》2007,18(10):1227-1230
A new isochroman-4-one,7,8-dihydroxy-3-methylisochroman-4-one was isolated from water soluble fraction of Musa sapientum L.Its structure was determined by spectroscopic evidences and its total synthesis has also been reported.The compound showed potent antihypertensive activity. 相似文献
3.
3,4-Epoxybisabola-7(14),10-dien-2-one,a natural sesquiterpoind,was first synthesized from(-)-carvone through 7 steps,in an overall yield of 35.9%.The key step was the allylation and then a substrate-directable epoxidation was committed successfully. 相似文献
4.
Jing Chao TAO Guo Qiang TIAN Yan Bing ZHANG Yu Qin FU Gui Fu DAI Ya WU 《中国化学快报》2005,16(11):1441-1444
In this paper, two new compounds, ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic acid 4 and its ethyl ester 5 were synthesized in good yield with a facile method that has never been reported. The mechanism of this reaction was discussed and the mono-hydroxymethylation of carbonyl compound with two α-hydrogens via Tollens' reaction was firstly achieved. Compounds 2-5 were tested for activity of inhibition against glycosidases, among which 5 displays good inhibition of β-glucosidase and α-mannase, respectively. 相似文献
5.
Chen Xi Zhang Li Jing Fang Fu Qiang Bi Yu Lin Li State Key Laboratory of Applied Organic Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou China 《中国化学快报》2008,19(3):256-258
Dihydromayurone (3), a key intermediate to synthesize (-)-thujopsene (1), was efficient enantiocontrolled synthesized from (+)-dihydrocarvone through 9 steps in an overall yield of 19.3%. The key step was the Simmons-Smith reaction. 相似文献
6.
A simple and high yielding method for the integration of 1,5-benzodiazepines integrated with 5-methyl- 2-oxo-3-phenyl-△^4-1,3,4-oxadiazolines in 75%-90% yield by microwave irradiation is devised. Microwave-accelerated reaction was compared with thermal method. All the compounds were characterized by physical, analytical and spectral (IR, 1^H NMR, MS) data. Title compounds were screened for preliminary pharmacological activities. 相似文献
7.
GuoQiangHU SongQiangXIE WenLongHUANG HuiBinZHANG 《中国化学快报》2005,16(6):723-726
To find new structural leading compounds for the research of the multidrug resistant of antibacterial agents, five novel 8-substituted phenyl-l-pyridin-3-yl-5H-bis[1, 2, 4] triazolo[3, 4-b;4‘,3‘-d] thiadiazines were prepared from the corresponding intermediates of 3-(5-substituted phenyl[1,3,4]oxadiazol-2-ylmethylsulfanyl)-5-pyridin-3-yl-[1,2,4]triazol-4-ylamines via intramolecular cyclization and the antibacterial activity in vitro against Gram-postive (G^ ) and Gramnegatiye (G) bacteria was primarily evaluated. 相似文献
8.
The crystal structure of the title compound(C17H12ClFO5,Mr=350.72) was determined by single-crystal X-ray diffraction.The crystal belongs to monoclinic,space group P21/c,with a=7.693(1),b=15.767(1),c=12.986(1),β=97.23(1)°,V=1562.6(2)3,Z=4,Dc= 1.491 g/cm3,λ(MoKα)=0.71073,F(000)=720,μ(MoKα)=0.280 mm-1,R=0.0563 and wR=0.1674.A total of 3592 unique reflections were collected,of which 2462 with Ⅰ2σ(Ⅰ) were observed.Five-membered lactone rings and hydroxyl-substituted phenyl rings are approximately coplanar with their dihedral angle of 4.1°.The dihedral angle between two different phenyl rings is 71.3°.To our interest,intramolecular O(1)-H(1)···O(4) hydrogen bonds could be found in each molecule.Intramolecular hydrogen bonds and intermolecular van der Waals force contribute to the stability of the structure. 相似文献
9.
A concise approach for the frst total synthesis of two naturally occurring flavanoids,()-malaysianone A(1)and()-tanariflavanones B(2),has been accomplished with total yields of 12.9%and 10.4%,respectively.The key steps were regioselective deprotection and regioselective synthesis of 5-formaldehyde-8-hydroxy-2-[40-methyl-30-penteneyl]-dihydro-1-benzopyran(8). 相似文献
10.
CrystalStructureofBis(3-hydroxy-2-pyridyl)disulfideChenXue-Tai;KangBei-Sheng;XuYong-Jin;HuYong-Han(StateKeyLaboratoryofStruct... 相似文献
11.
A rapid and efficient method was established for the synthesis of indoloquinolinone and its analogues using acid-promoted cyclization in the present of PPA. All the reactions were completed in good yields in lOmin under microwave irradiation. 相似文献
12.
HU Yang-Gen DING Ming-Wu 《结构化学》2008,27(1):21-24
The crystal structure of the new title compound 2-ethoxy-3-n-butyl- benzofuro[2,3d]pyrimidin-4(3H)-one (C16H18N2O3, Mr = 286.32) has been prepared and determined by singlecrystal X-ray diffraction. The crystal is of monoclinic, space group P21/c with a = 13.7167(14), b = 13.113(1), c = 8.378(1) A, β = 98.992(2)^o, V = 1488.4(3) A^3, Z = 4, Dc = 1.278, F(000) = 608, μ = 0.089 mm^-1, MoKa radiation (2 = 0.71073), R = 0.0498, wR = 0.1238 for 2336 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals that all ring atoms in the benzo[4, 5]furo [2,3-d] pyrimi- dinone moieties are almost coplanar. 相似文献
13.
14.
ZHANG Xin-Shuai ZOU Jian-Ping② ZENG Run-Sheng AN Li-Tao 《结构化学》2005,24(3):295-298
1 INTRODUCTION Many organic substances of interest contain vari-ous types of rings and it becomes important to ex-plore and develop new approaches to appropriatelyfunctionalize medium and large rings. Free radicalcyclization reaction is a new strategy to constructdifferent types of cyclic compounds including biolo-gically active natural products and pharmaceuti-cals[1~4], and nowadays it is one of the importantresearch fields of organic chemistry. Up to date, noreport on the radical cycl… 相似文献
15.
LU Xing-Qianga PI Xiang-Dongb SU Cheng-Yonga a 《结构化学》2005,24(10):1176-1180
1 INTRODUCTION N,N?-4-aminomethyl-pyromellitic diimide (4-pmpmdwas firstly obtained[1] in 1989 as one of the bypro-ducts by refluxing equimolar quantities of pyrome-llitic anhydride, n-hexylamine and 4-aminomethyl py-ridine in dry DMF to assemble electronic donor-spa-cer-acceptor systems, but its structure and coordina-tion chemistry did not receive attention at that time.For 4-pmpmd, the entity of two methylene groups(-CH2-) between the rigid pyromellitic diimide (PMDcore and two fre… 相似文献
16.
A novel camptothecin analogue, 9-methyl-10-hydroxycamptothecin (4), was unexpectedly synthesized from 10-hydroxycamptothecin in two steps. The key step included an efficient Mannich-type reaction. The overall yield was 47.2%. An ether analogue of 4, 9-methyl-10-benzylaminomethoxycamptothecin (5), was also prepared. These new camptothecin analogues were evaluated for in vitro cytotoxicity against four human cancer cell lines, and exhibited more potent antitumor activities than contrals camptothecin and topotecan against several cancer cells. 相似文献
17.
YuKunGUAN PingLI LiJingFANG YuLinLI 《中国化学快报》2005,16(6):711-712
The first total synthesis of 3-oxo-11, 12, 13-trihydroxyeudesm-4-ene, a highly oxygenated natural eudesmane, was described. 相似文献
18.
The title compound [2-hydroxy-5-(4-hydroxy-3-phenyliminomethyl-benzyl)-benzylidene]-phenyl-amine (C27H22N2O2, Mr = 406.47) was synthesized by 5,5′-methylene-bissalicylal- dehyde with aminobenezene, and its crystal structure was determined by single-crystal X-ray diffraction. The crystal belongs to the monoclinic system, space group C2/c with a = 4.4026(6), b = 1.501(13), c = 0.95818(12) nm, β = 90.868(2)°, V= 4.2813(9) nm^3, Z= 8, Dc= 1.292 g/cm^3,μ = 0.010, F(000) = 1744, R = 0.0576 and wR = 0.1450 for 3766 observed reflections with I 〉 2σ(I). X-ray analysis reveals that the molecule has a pair of intramolecular OH…N hydrogen bonds. 相似文献
19.
Tserfas M. O. Levina I. S. Kuznetsov Y. V. Scherbakov A. M. Mikhaevich E. I. Zavarzin I. V. 《Russian Chemical Bulletin》2020,69(3):552-557
Russian Chemical Bulletin - A directed synthesis of two progesterone metabolites, allopregnanolone and 3a-hydroxy-pregn-4-en-20-one, from Δ16-pregnanolone and progesterone, respectively, was... 相似文献