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1.
A new approach to 1‐phosphabicyclo[3.3.0]octane compounds starts from the reaction of 4‐chloro‐hepta‐1.6‐diene with Mg in THF. No Grignard rearrangement is observed. The Grignard reagent is converted into 1‐allyl‐3‐butenylphosphonous dichloride followed by reduction with LiAlH4. Cis‐1‐phosphabicyclo[3.3.0]octane has been prepared by radical‐initiated cyclization of 1‐allyl‐3‐butenylphosphane. The bicyclic phosphane is characterized by analytical data as well as 31P and 13C NMR measurements and the reactionswith NO, S8, KSeCN, CH3I, Ni(CO)4 and HSO3F, respectively.  相似文献   

2.
Phosphorus(V)-Hydrazine-Sulfur(IV) Heterocycles with Twist-Boat Conformation . Unlike the corresponding unsubstituted compounds N-ethoxycarbonyl-substituted dihydrazidophosphoric acid derivatives do not react with thionylchloride under redoxdecomposition but yield sulfur containing sixmembered rings. In solution (NMR spectra) as well as in the crystal (X-ray structure analysis) the rings adopt unusual twist-boat conformations. Due to the rather bulky substituents high energies of interconversion between enantiomeric twist-forms are found: 75 ± 2 kJ/mol.  相似文献   

3.
A Cyclic Methylenediphosphinic Acid: 1,3‐Dihydroxy‐1,3‐dioxo‐1,2,3,4‐tetrahydro‐1λ5,3λ5‐[1,3]diphosphinine Strong acids protonate 1,3‐bis(dimethylamino)‐1λ5,3λ5‐[1,3]diphosphinine ( 5 ) to give the corresponding cation. The protonation is followed by hydrolytic cleavage of the dimethylamino groups resulting in the formation of the cyclic methylenediphosphinic acid ( 6 ).  相似文献   

4.
The paper deals with the structure elucidation of (4aRS,5aRS,9aRS,11aRS)-perhydro-5a,11a-epoxydibenz[b,f]oxepin-4a-ol ( 6 ), which is unexpectedly formed from 2-dimethylaminomethylcyclohexanone hydrochloride ( 1 ·HCl) in the presence of phenylguanidine in boiling ethanol. In detail, two molecules of 2-methylenecyclohexanone (generated from 1 by elimination of dimethylamine) afforded via Diels–Alder reaction, subsequent addition of water and ring closure a product C14H22O3, which finally proved to be the title compound. The structure of the tetracyclic hemiacetal 6 was deduced from one- and two-dimensional NMR experiments (1D TOCSY, DEPT-135, 1H,1H-COSY, gs-HSQC, gs-HMBC, gs-HSQC-TOCSY). In particular, the one-dimensional selective TOCSY and the gradient-selected HSQC-TOCSY, performed as a pseudo-3D experiment without the evolution period in the TOCSY part, proved to be very helpful for the unambiguous assignment of signals in overcrowded regions. NOE data confirmed the stereochemistry of epoxydibenzoxepinol 6 . Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

5.
以两种不同取代的2-氨基二苯甲酮为原料,氯苯为溶剂,BF3-Et2O为脱水剂,通过分子间脱水一步环化缩合制备非对称二苯并[b,f][1,5]二氮杂环辛四烯衍生物。运用HPLC监控反应过程,优化合成工艺,得到最佳反应条件为:等物质的量的两种不同取代2-氨基二苯甲酮和BF3-Et2O,在氯苯中回流反应12 h。化合物4a^4c为新化合物,其结构经1H NMR,13C NMR和MS(ESI)表征。  相似文献   

6.
The geometry of dibenzoazepine analogues—typical multifunctional drugs—was investigated to find the geometrical parameters sensitive to the substitution of the central seven-membered ring. Exploration of the crystal structure database (CSD) shows that the geometrical parameter sensitive to the substitution of the carbon atom distance of the central ring not included in the aromatic rings to the plane through the carbon atoms common for the central ring and the aromatic side rings. Presence of the double bond in the central ring was reflected in its partial aromaticity expressed by the HOMED parameter. Some derivatives of 5H-dibenzo[b,f]azepine with flat conformation of the central ring are characterized by mobility of the electron density comparable to the mobility in the aromatic side rings. Influence of the surrounding on the investigated compounds was confirmed by comparison of the optimized molecules and the molecules in the crystal state where the packing forces can influence the molecular geometry.  相似文献   

7.
A new four‐component synthesis of spiro[4H‐indeno[1,2‐b]pyridine‐4,3′‐[3H]indoles] and spiro[acenaphthylene‐1(2H),4′‐[4H‐indeno[1,2‐b]pyridines] by the reaction of indane‐1,3‐dione, 1,3‐dicarbonyl compounds, isatins (=1H‐indole‐2,3‐diones) or acenaphthylene‐1,2‐dione, and AcONH4 in refluxing toluene in the presence of a catalytic amount of pyridine is reported.  相似文献   

8.
Dibenzo[b, f]oxepine derivatives are an important scaffold in natural, medicinal chemistry, and these derivatives occur in several medicinally relevant plants. Two dibenzo[b, f]oxepines were selected and connected with appropriate fluorine azobenzenes. In the next step, the geometry of E/Z isomers was analyzed using density functional theory (DFT) calculations. Then the energies of the HOMO and LUMO orbitals were calculated for the E/Z isomers to determine the HOMO-LUMO gap. Next, modeling of the interaction between the obtained isomers of the compounds and the colchicine α and β-tubulin binding site was performed. The investigated isomers interact with the colchicine binding site in tubulin with a part of the dibenzo[b, f]oxepine or in a part of the azo switch, or both at the same time. Based on the UV-VIS spectra, it was found that in the case of compounds with an azo bond in the meta position, the absorption bands n→π* for both geometric isomers and their separation from π→π* are visible. These derivatives therefore have the potential to be used in photopharmacology.  相似文献   

9.
10.
Dialkyl- and diarylammonium ions are able to form complexes with α-cyclodextrin and cucurbit[6]uril. These amines are able to complex two guest molecules simultaneously resulting in the formation of homogeneous or heterogeneous 1:2 (ratio of dialkylammonium to ligand) complexes. The stability constants and reaction enthalpies for the formation of 1:1 complexes have been measured using potentiometric and calorimetric titrations. Differences between the values obtained by these methods can be attributed to solvent composition. Only for the 1:2 complex formation with cucurbit[6]uril, the ligands influenced each other. The polar carbonyl groups at each portal of the cucurbit[6]urils interacted simultaneously with the protonated amino group resulting in an electrostatic repulsion between both molecules. No further interactions between two complexed molecules of α-cyclodextrin or cucurbit[6]uril and α-cyclodextrin were observed. The absence of polar groups in the case of α-cyclodextrin led to unaffected formation of homogeneous and even heterogeneous 1:2 complexes.  相似文献   

11.
Salts of Halogenophosphoric Acids. XIX Formation and Identification of Stable Intermediates on the Reaction of Fluoride with Phosphorus Oxychloride By reaction of POCl3 with fluorides of tertiary amines in the presence of the free amines the oxo-fluorophosphates [F2P(O? O? PF5)]?, [OPF5]2?, and [OPF4]? are formed as intermediates on the way to [PF6]?. The compounds were characterized by NMR spectroscopy.  相似文献   

12.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XVII [1] [Co(g5‐Me5C5)(g3tBu2PPCH–CH3)] from [Co(g5‐Me5C5)(g2‐C2H4)2] and tBu2P–P=P(Me)tBu2 [Co(η5‐Me5C5)(η3tBu2PPCH–CH3)] 1 is formed in the reaction of [Co(η5‐Me5C5)(η2‐C2H4)2] 2 with tBu2P–P 4 (generated from tBu2P–P=P(Me)tBu2 3 ) by elimination of one C2H4 ligand and coupling of the phosphinophosphinidene with the second one. The structure of 1 is proven by 31P, 13C, 1H NMR spectra and the X‐ray structure analysis. Within the ligand tBu2P1P2C1H–CH3 in 1 , the angle P1–P2–C1 amounts to 90°. The Co, P1, P2, C1 atoms in 1 look like a „butterfly”︁. The reaction of 2 with a mixture of tBu2P–P=P(Me)tBu2 3 and tBu–C?P 5 yields [Co(η5‐Me5C5){η4‐(tBuCP)2}] 6 and 1 . While 6 is spontaneously formed, 1 appears only after complete consumption of 5 .  相似文献   

13.
The ambident electrophilic character of the 5-bromo-2-hydroxychalcones and the binucleophilic nature of 2-aminothiophenol were exploited to construct the 2-aryl-4-(4-bromo-2-hydroxyphenyl)benzo[1,5]thiazepines. The structures and conformation of these 2-aryl-4-(4-bromo-2-hydroxyphenyl)benzo[1,5]thiazepines were established with the use of spectroscopic techniques complemented with a single crystal X-ray diffraction method. Both 1H-NMR and IR spectroscopic techniques confirmed participation of the hydroxyl group in the intramolecular hydrogen-bonding interaction with a nitrogen atom. SC-XRD confirmed the presence of a six-membered intramolecularly hydrogen-bonded pseudo-aromatic ring, which was corroborated by the DFT method on 2b as a representative example in the gas phase. Compounds 2a (Ar = -C6H5), 2c (Ar = -C6H4(4-Cl)) and 2f (Ar = -C6H4(4-CH(CH3)2) exhibited increased inhibitory activity against α-glucosidase compared to acarbose (IC50 = 7.56 ± 0.42 µM), with IC50 values of 6.70 ± 0.15 µM, 2.69 ± 0.27 µM and 6.54 ± 0.11 µM, respectively. Compound 2f, which exhibited increased activity against α-glucosidase, also exhibited a significant inhibitory effect against α-amylase (IC50 = 9.71 ± 0.50 µM). The results of some computational approaches on aspects such as noncovalent interactions, calculated binding energies for α-glucosidase and α-amylase, ADME (absorption, distribution, metabolism and excretion) and bioavailability properties, gastrointestinal absorption and blood–brain barrier permeability are also presented.  相似文献   

14.
We report the syntheses and characterization of novel 3,7-bicycl[3.3.1]bispidines possessing an imidazolpropyl group attached to N-3, and at N-7 a Boc group, as well as a benzoylated-oximated group at C-9. These compounds were complexed with β-cyclodextrin [β-CD] and evaluated as seed protectors of selected wheat seedlings. Using strong acid, condensations of N-substituted piperidones with the appropriate imidazolpropyl groups at N-3 and N-7 led to bispidinones 6 and 7. These intermediates were reduced to the corresponding 3,7-diazabicyclo[3.3.1]nonane targets. The oxime at C-9 was benzoylated to yield 13. Heating these 3,7-diazabicyclo[3.3.1]nonanes in ethanol with β-CD generated the complexes required. We investigated the ability of such complexes as coatings on seedlings to protect and stimulate growth of three varieties of wheat, namely Kazakhstanskaya-10, Severyanka, and Miras. The complex of 3-[3-(1H-imidazol-1-yl)propyl]-7-(3-methoxypropyl)-3,7-diazabicyclo[3.3.1]nonane (2) promoted growth in the root systems of all three wheat varieties by more than 30% in Kazakhstanskaya-10, 30% in Severyanka and 8.5% in Miras. A complex of 3-Boc-7-[3-(1H-imidazol-1-yl)propyl]-3,7-diazabicyclo[3.3.1]nonane (9) increased both shoot and root length in only the Severyanka variety. The complex of 3-(3-butoxypropyl)-7-[3-(1H-imidazol-1-yl)propyl]-3,7-diazabicyclo[3.3.1]nonane (11) stimulated both shoot growth (0.8%, 12.3%, 13.5%) and root growth (12.3%, 9.4%, 21.7%) in all three varieties of wheat, respectively. The nature of substituents on the bispidine affect the activity. Solid complexes (1:1) were generated as powders which melted above 240 °C (dec) and were characterized via elemental analyses as 1:1 complexes.  相似文献   

15.
In the presence of base, 3-subslituted 4-fonnyl- and 4-acetylsydnones decarbonylated to afford the corresponding 3-substituted sydnones. The Claisen-Schmidt reaction occurred between 3-substituted 4-for-mylsydnones and methyl ketone (such as 4-acetylsydnones, acetone and acetophenone) in dilute basic solution or electrogenerated basic (EGB) solution.  相似文献   

16.
Treatment of 4-arylamino-4-thioxo-2-butanones with methylhydrazine in acetic acid gives 5-arylamino-1,3-dimethylpyrazoles which are readily halogenated in the 4 position. The thermal decomposition of 3-anilino-1,2,5-trimethyl-1H-pyrazolium chloride gives 1,3-dimethyl-5-phenylaminopyrazole and 1,5-dimethyl-3-phenylaminopyrazole in the approximate ratio of 1:1.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 120–126, January, 2005.  相似文献   

17.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes XXI The Influence of the PR3 Ligands on Formation and Properties of the Phosphinophosphinidene Complexes [{η2tBu2P–P}Pt(PR3)2] and [{η2tBu2P1–P2}Pt(P3R3)(P4R′3)] (R3P)2PtCl2 and C2H4 yield the compounds [{η2‐C2H4}Pt(PR3)2] (PR3 = PMe3, PEt3, PPhEt2, PPh2Et, PPh2Me, PPh2iPr, PPh2tBu and P(p‐Tol)3); which react with tBu2P–P=PMetBu2 to give the phosphinophosphinidene complexes [{η2tBu2P–P}Pt(PMe3)2], [{η2tBu2P–P}Pt(PEt3)2], [{η2tBu2P–P}Pt(PPhEt2)2], [{η2tBu2P–P}Pt(PPh2Et)2], [{η2tBu2P–P}Pt(PPh2Me)2], [{η2tBu2P–P}Pt(PPh2iPr], [{η2tBu2P–P}Pt(PPh2tBu)2] and [{η2tBu2P–P}Pt(P(p‐Tol)3)2]. [{η2tBu2P–P}Pt(PPh3)2] reacts with PMe3 and PEt3 as well as with tBu2PMe, PiPr3 and P(c‐Hex)3 by substituting one PPh3 ligand to give [{η2tBu2P1–P2}Pt(P3Me3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3Ph3)(P4Me3)], [{η2tBu2P1–P2}Pt(P3Et3)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3MetBu2)(P4Ph3)], [{η2tBu2P1–P2}Pt(P3iPr3)(P4Ph3)] and [{η2tBu2P1–P2}Pt(P3(c‐Hex)3)(P4Ph3)]. With tBu2PMe, [{η2tBu2P–P}Pt(P(p‐Tol)3)2] forms [{η2tBu2P1–P2}Pt(P3MetBu2)(P4(p‐Tol)3)]. The NMR data of the compounds are given and discussed with respect to the influence of the PR3 ligands.  相似文献   

18.
2, 4‐Dimethylpenta‐1, 3‐diene and 2, 4‐Dimethylpentadienyl Complexes of Rhodium and Iridium The complexes [(η4‐C7H12)RhCl]2 ( 1 ) (C7H12 = 2, 4‐dimethylpenta‐1, 3‐diene) and [(η4‐C7H12)2IrCl] ( 2 ) were obtained by interaction of C7H12 with [(η2‐C2H4)2RhCl]2 and [(η2‐cyclooctene)2IrCl]2, respectively. The reaction of 1 or 2 with CpTl (Cp = η5‐C5H5) yields the compounds [CpM(η4‐C7H12)] ( 3a : M = Rh; 3b : M = Ir). The hydride abstraction at the pentadiene ligand of 3a , b with Ph3CBF4 proceeds differently depending on the solvent. In acetone or THF the “half‐open” metallocenium complexes [CpM(η5‐C7H11)]BF4 ( 4a : M = Rh; 4b : M = Ir) are obtained exclusively. In dichloromethane mixtures are produced which additionally contain the species [(η5‐C7H11)M(η5‐C5H4CPh3)]BF4 ( 5a : M = Rh; 5b : M = Ir) formed by electrophilic substitution at the Cp ring, as well as the η3‐2, 4‐dimethylpentenyl compound [(η3‐C7H13)Rh{η5‐C5H3(CPh3)2}]BF4 ( 6 ). By interaction of 2, 4‐dimethylpentadienyl potassium with 1 or 2 the complexes [(η4‐C7H12)M(η5‐C7H11)] ( 7a : M = Rh; 7b : M = Ir) are generated which show dynamic behaviour in solution; however, attempts to synthesize the “open” metallocenium cations [(η5‐C7H11)2M]+ by hydride abstraction from 7a , b failed. The new compounds were characterized by elemental analysis and spectroscopically, 4b and 5a also by X‐ray structure analysis.  相似文献   

19.
In this study, we describe systematic preparation of a series of aryl-substituted pyridine derivatives. The 1,5-dicarbonyls (3a–i) were prepared in the solvent-free conditions starting from chalcone derivatives (1a–i). The target compounds, 4-aryl-2-(thiophen-3-yl)-6,7-dihydro-5H-cyclopenta[b]-pyridine derivatives (5a–i), were synthesized by a cyclization reaction of the 1,5-dicarbonyls (3a–i) with ammonium acetate (NH4OAc) in acetic acid. The characterization of synthesized compounds was proved by elemental analyses, infrared, mass spectrometry, and 1H and 13C NMR spectroscopy.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]  相似文献   


20.
研究了1-芳基-4-乙氧羰基-5-氨基-1,2,3-连三唑(1)同甲酰胺、异氰酸磺酰氯以及内酰亚胺醚等的反应,制得5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(2a-c)、5-N-甲基-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4-酮(3a-c)、1-芳基-4-乙氧羰基-5-脲基-1,2,3-连三唑(4a,b)、5-H-1-芳基-1,2,3-连三唑[4,5-e]嘧啶-4,6-二酮(5_(a,b))、1-苯基-1,2,3-连三唑[4,5-e]哌啶[1,2-b]嘧啶-4-酮(6a)、1-苯基-1,2,3-连三唑[4,5-e]氢化吖辛因[1,2-b]嘧啶-4-酮(7a),并经元素分析、红外、核磁共振以及质谱等方法确认了它们的结构,初步筛选了其代表特的生物活性.  相似文献   

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