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1.
The synthesis of quinoline derivatives that contain a fluorogenic grouping by condensation of 8-(N-methyl-N-carbobenzoxy)aminomethylquinoline-5-carboxylic acid azide with N-(6-aminohexyl)-5-dimethylaminonaphthalenesulfonamide is described. The resulting carboxamide was subjected to hydrogenolysis, and subsequent reaction with propargyl bromide led to the title compound.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No, 6, pp. 789–792, June, 1982.  相似文献   

2.
Starting from the aldehydes 2 and 9 the acetylene 16 is prepared via the borane 15 by means of a combined Wittig reaction-hydroboration reaction sequence. 16 may be converted into the (E)-6,(Z)-11-hexadecadienylacetate (18) and the corresponding aldehyde 19. The synthetic route proceeds with high stereospecifity (isomeric purity of 18 and 19 ? 97%).  相似文献   

3.
Two new 6-substituted 2,2′-bipyridines, L, 6-(2-tolyl)bipy, L1, and 6-(2,6-xylyl)bipy, L2, have been synthesized. Their reactions with Na2[PdCl4] or {Pd(OAc)2} afford either 1:1 adducts [Pd(L)X2] (X=Cl, OAc) or five-membered cyclometallated derivatives [Pd(L1-H)X] arising from C(sp2)H activation. From the chloro-alkyl intermediates [Pd(L)(Me)Cl], in the presence of Na[BAr′4] (Ar′=3,5-(CF3)2C6H3), cationic species [Pd(L)(Me)(S)]+ (L=L1, L2; S=CH3CN) can be obtained. At variance, in less coordinating solvents, e.g. dichloromethane, unexpected activation of a C(sp3)H bond occurs with loss of methane, to afford 6-membered cyclometallated derivatives. The latter species were isolated as [Pd(L-H)(PPh3)][BAr′4].  相似文献   

4.
Novel (5R,8S,10R)-6-(allyloxy)- and (5R,8S,10R)-6-(propyloxy)ergolines have been synthesized by use of a Meisenheimer [2,3]-sigmatropic rearrangement of a (5R,8S,10R)-6-allyl-ergoline N6-oxide as key step.  相似文献   

5.
用密度泛函方法在B3LYP/6-31G*水平上研究了顺-8-三甲基锡烷基-6-辛烯醛分子内环化反应的机理,通过振动分析和内禀反应坐标对过渡态进行了确认,解析了三种反应途径.结果表明,反应具有很强的立体选择性,虽然-OSn(CH3)3和-C2H3基团均处于环的平伏位,是最稳定的产物构型,但是主要产物是经过活化能最低,且具有两个六元环椅式构象的过渡态形成的,主要产物中-OSn(CH3)3基团处于环的直立位.该结果与实验事实一致.  相似文献   

6.
A high-performance liquid chromatographic method for the simultaneous determination of both enantiomers of naproxen and its metabolite 6-O-desmethylnaproxen has been developed. The separation is performed on a column containing alpha 1-acid glycoprotein as the chiral selector. The method has been used for the determination of the enantiomeric purity of the drug substance and the metabolite, and for the simultaneous determination of all four compounds in biological fluids.  相似文献   

7.
The structures of 8-G-1-(p-YC(6)H(4)Se)C(10)H(6) (1 (G = Cl) and 2 (G = Br): Y = H (a), OMe (b), Me (c), Cl (d), Br (e), COOEt (f), and NO(2) (g)) were investigated by X-ray crystallographic analysis, NMR spectroscopy, and ab initio MO calculations. The structures of all members in 1 and 2 are concluded to be type B, which is in striking contrast to the type A structure for 4d-g (4 (g(n)), where G = H). The Se-C(i) bond of the p-YC(6)H(4)Se group in 8-G-1-(p-YC(6)H(4)Se)C(10)H(6) is almost perpendicular to the naphthyl plane in type A, and it is located on the plane in type B. The chlorine and bromine substitution at the 8-position in 1 and 2 dramatically changes the type A structure of 4 (g(n)) to type B. The nonbonded G- - -Se-C 3c-4e type interaction must contribute to stabilize the type B structure. The type B structure in 1 and 2 should also be more stabilized than the same structure in 4 by the 3c-4e type interaction: The structure of 4b is type B in the crystals and type B would be more stable for 4c and might be for 4a in solutions. Ab initio MO calculations are performed on 8-G-1-(p-YC(6)H(4)Se)C(10)H(6), 8-G-C(10)H(6)SeH-1, and models HG- - -SeH(2), where G = Cl, Br, and F, to clarify the reason for the dramatic change in the structures. The type B structure is optimized to be more stable than the type A for all species examined, which supports the observations. The energy differences between type B and type A are larger for the models than for the naphthalenes. While the superiority of the type B for the former is Br > Cl > F, that of the latter is Br approximately Cl >/= F. These results show that the main factor of the structural change from type A to type B is the nonbonded G- - -Se-C 3c-4e interaction. The electronic effect of halogens through the naphthalene pi-framework would also contribute to some extent, although the direct comparison of the evaluated values between the naphthalene systems and the models is not so easy. Factors to stabilize the two structures of 1, 2, 4, and 8-(MeSe)-1-(p-YC(6)H(4)Se)C(10)H(6) are reexamined from a viewpoint of the nonbonded G- - -Se-C 3c-4e interaction (G dependence), together with the electronic effect of Y (Y dependence).  相似文献   

8.
When (?)-Δ8-6a, 10a-trans-THC (THC = Tetrahydrocannabinol), in the form of its diacetate, was irradiated in the presence of oxygen and a sensitizer, followed by reduction with NaBH4, three allylic alcohols were formed: (?)-8α-and (?)-8β-hydroxy-Δ9,11-THC (proportion 3:1) and (?)-9α-hydroxy-Δ7,8-THC. Acetylation of the epimeric 8-hydroxy-compounds with Ac2O/pyridine gave the corresponding diacetates. When (?)-Δ8-6a, 10a-trans-THC, in the form of its tetrahydropyranyl derivative, was heated with m-chloroperbenzoic acid, the two epimeric 8,9-epoxides were formed in equal amounts. These compounds, on treatment with butyllithium, afforded (?)-8α- and (?)-8β-hydroxy-Δ9,11- 6a, 10a-trans-THC-tetrahydropyranylether. After removing the protecting group and treatment with Ac2O/pyridine the same diacetates, as formed by photooxygenation of (?)-Δ8-THC-acetate, were obtained as a 1:1-mixture. On heating these epimeric diacetates to 290° they underwent allylic rearrangement to (?)-11-acetoxy-Δ8-THC-acetate. From this (?)-11-hydroxy-Δ8-6a, 10a-trans-THC was obtained by treatment with LiAlH4.  相似文献   

9.
10.
Todorov I  Sevov SC 《Inorganic chemistry》2004,43(20):6490-6494
The title compounds were prepared by direct reactions of the corresponding elements at high temperature. They are isostructural with each other (monoclinic, P2(1)/m, Z = 2; Na(8)BaPb(6), a = 13.116(4), b = 5.351(1), and c = 16.166(5) A, beta = 108.07(2) degrees; Na(8)BaSn(6), a = 12.897(4), b = 5.362(1), and c = 16.826(5) A, beta = 108.19(2) degrees; Na(8)EuSn(6), a = 12.912(2), b = 5.220(1), and c = 15.721(2) A, beta = 108.09(1) degrees ) and contain isolated, flat, and aromatic pentagonal rings of Sn(5)(6)(-) and Pb(5)(6)(-) as well as isolated anions of Sn(4)(-) and Pb(4)(-). According to four-probe conductivity measurements, the tin compounds, Na(8)BaSn(6) and Na(8)EuSn(6), are semiconducting with band gaps of 0.11 and 0.09 eV, respectively, and are therefore electronically balanced. Magnetic measurements show that Na(8)BaSn(6) is diamagnetic while Na(8)EuSn(6) is paramagnetic and undergoes two transitions at low temperatures.  相似文献   

11.
Six side chain analogs of the highly active antimalarial agent 8-(4-amino-1-methylbutylamino)-6-methoxy-4-methyl-5-(3-trifluoromethylphenoxy)quinoline (I) were prepared and evaluated for blood and tissue schizonticidal activity. Although most examples were markedly superior to primaquine none was superior to the parent compound I.  相似文献   

12.
New 2-chloroethylthio derivatives of sym-triazine were obtained by the reaction of mercapto-sym-triazines and dichloroethane. It was established that these chlorides undergo cyclization to give 2-dialkylamino-4-oxo(thioxo)-4,5,6,7-tetrahydrothiazolo [1,2-a]-sym-triazines, the structure of which was confirmed by PMR and mass-spectral data, at moderate temperatures.See [7] for Communication 7.Translated f rom Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1275–1278, September, 1981.  相似文献   

13.
[structures: see text] Both (2S,5R,6R)- and (2S,5R,6S)-6-hydroxy-8-(1-decynyl)benzolactam-V8 were designed and synthesized as PKC modulators. Biological assays reveal the (6R)-ligand to be 20-fold more potent than its (6S)-counterpart in binding to PKC alpha.  相似文献   

14.
The biotransformation of (R)-(+)- and (S)-(-)-citronellol by fungi was studied. For screening experiments, solid-phase microextraction (SPME) was used as analytical sampling technique. It was found that sporulated surface cultures of Aspergillus niger were able to convert the substrate into cis- and trans-rose oxides and nerol oxide. The relative contents in the headspace SPME extract of the three bioconversion products cis- and trans-rose oxide and nerol oxide were up to 54, 21 and 12%, respectively. Rose oxide is found in minor amounts in some essential oils, such as Bulgarian rose oil and geranium oil and contributes to its unique odor. It is one of the most important fragrance materials in perfumery in creating rosy notes. Other bioconversion products were 6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, limonene, terpinolene, linalool and alpha-terpineol. These bioconversion reactions were confirmed by sporulated surface cultures on larger scale and sampling by dynamic headspace sweep and steam distillation solvent extraction. The same conversions were noticed with A. tubingensis and Penicillium roqueforti. This bioconversion was enantioselective since more of the chiral cis- than trans-rose oxide was obtained (cisitrans ratio up to 95/5). Submerged liquid cultures of P. roqueforti yielded two unidentified metabolites after conversion of citronellol (yield up to 5%). The stability and acid-catalyzed conversion of citronellol was also investigated. No chemical oxidation or auto-oxidation products were detected in acidified liquid control broths up to pH 3.5. However, when control tests were run with solid media, acid-catalyzed conversion of the substrate to small amounts of cis- and trans-rose oxides, nerol oxide, linalool and alpha-terpineol was observed at pH 3.5 and when heat treatment (steam distillation solvent extraction) was applied.  相似文献   

15.
《Tetrahedron: Asymmetry》1999,10(14):2739-2747
The synthesis of (+)-(R)-5-hydroxy-6-hydroxymethyl-7-methoxy-8-methylflavanone is described. A new chromylation method of β-ketosulfoxide 9 leading to the Michael acceptor 12 has been developed. Dilithium tetrachlorocuprate was shown to be a very efficient catalyst for the conjugate addition reaction of phenyl magnesium bromide to the α,β-unsaturated sulfoxide 12. The instability of the obtained adducts 10 represents a limitation in terms of yield. It was confirmed that the natural flavanone leridol does not possess the structure of title compound 1.  相似文献   

16.
《Tetrahedron》1988,44(19):6153-6168
Enantiospecific syntheses of (6R,7S,8aR)-6,7-dihydroxy-indolizidine (3) and (6R,7R,8S,8aR)-6,7,8-trihydroxy-indolizidine (4) from methyl 2-azido-4,6-O-benzylidene-2-deoxy-α-D-altropyranoside (7) are reported. The two synthetic indolizidines (3) and (4) have been tested against a wide range of enzymes.  相似文献   

17.
18.
The synthesis of mono-6-(3-methylimidazolium)-6-deoxyperphenylcarbamoyl-beta-cyclodextrin chloride (MPCCD) and its application in chiral stationary phases (CSPs) for high-performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC) are being reported. This chiral selector is coated onto silica gel in different weight percentages (15, 20 and 35%, w/w) to obtain CSPs having different loading content. These new chiral stationary phases are tested using normal-phase HPLC for enantioseparation of racemic aromatic alcohols. Indeed, the enantiodiscrimination abilities of these CSPs are found to be influenced by the loading content of the chiral selector. Among the three columns (MPCCD-C15, MPCCD-C20 and MPCCD-C35), the best enantioseparation results are obtained using a column containing 20% (w/w) of MPCCD (MPCCD-C20). The resolution (R(s)) obtained for p-fluorophenylethanol, p-chlorophenylethanol, p-bromophenylethanol, p-iodophenylethanol and p-fluorophenyl-3-buten-1-ol using MPCCD-C20 ranges from 3.83 to 5.65. Good enantioseparation results are obtained for these analytes under SFC separation conditions using the MPCCD-C20 column.  相似文献   

19.
Ion-exclusion chromatography is a well established technique for the analysis of achiral ionic species, but it has rarely been applied to chiral analytes. In this paper enantioselective ion-exclusion separations were developed on two commercially available HPLC phases: Chirobiotic TAG, based on teicoplanin aglycone, and Opticrown RCA (+), based on (+)-(18-crown-6)-2,3,11,12-tetracarboxylic acid. Chirobiotic TAG columns have a carboxylic acid group on the chiral ligand, which can be partially ionized to exclude anionic analytes by ionic repulsion. Under acidic conditions Opticrown columns have a cationic sublayer generated from the aminopropyl base silica that excludes cationic analytes. Both columns demonstrate a large dependence of efficiency on flow-rate, with the highest efficiencies at 0.1 ml/min on a 4.6 mm inner diameter column.  相似文献   

20.
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