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1.
V. G. Kharchenko A. A. Rassudova T. I. Krupina S. K. Klimenko T. P. Chepurnenkova 《Chemistry of Heterocyclic Compounds》1970,6(3):315-318
On reaction with Grignard compounds, sym-octahydrothioxanthylium and 9-methyl-symoctahydrothioxanthylium perchlorates form 9-mono- and 9, 9-disubstituted sym-octahydrothioxanthenes. The reactions of the new sym-octahydrothioxanthene with perchloric acid and ferric chloride has been studied. The elimination of the benzyl group of 9-benzyl-sym-octahydrothioxanthene on salt formation has been observed.For part VI, see [1]. 相似文献
2.
In the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 9-triptycylisothiocyanate has been synthesized in 91% yield from carbon disulfide and sterically hindered 9-triptycylamine at room temperature. 9-Triptycylisothiocyanate can be further converted to 1-benzyl-3-(9-triptycyl)thiourea. (10-Amino-9-triptycyl)carboxylic acid has also been successfully synthesized via a three-step route starting from methyl 10-nitroanthracene-9-carboylate. Its amino and carboxylic groups can undergo acetylation and amidation, respectively. 相似文献
3.
Vibrational spectroscopy of jet-cooled 9-fluorenemethanol and its clusters 9-fluorenemethanol-H2O, 9-fluorenemethanol-CH3OH, 9-fluorenemethanol-C2H5OH, and 9-fluorenemethanol-C3H7OH has been carried out using an IR-UV double-resonance method. The spectrum of the OH stretching vibration, v(OH), has been measured for the 9-fluorenemethanol monomer and for each of the clusters. Two conformers of 9-fluorenemethanol, symmetric (sym) and unsymmetric (unsym), have been identified using a combination of spectroscopy and quantum chemical calculations with B3LYP and HF methods using the 6-31G(d) basis set. Vibrational dynamics resulting from IR excitation has also been studied using the S0-S1 transition probed by a nanosecond-time-delayed UV laser. The data suggest that isomerization occurs as a result of the IR excitation, but the breadth of the probe spectra makes an unequivocal conclusion difficult. The effect of hydrogen bonding on the v(OH) of 9-fluorenemethanol has also been studied in clusters with water, methanol, ethanol, and propanol by measuring the IR spectra. Cluster dissociation dynamics have also been studied following IR excitation. It is observed that upon excitation of the cluster of a particular conformation the monomer product is generally produced in both conformer forms. Energetic considerations indicate that isomerization occurs before dissociation. 相似文献
4.
Adenine acidification as a consequence of simultaneous PtII binding to N1 and N7 facilitates deprotonation of the exocyclic N(6)H2 group and permits PtII migration from N1 to N6 under mild conditions. Starting from the trinuclear complex cis-[(NH3)2Pt(N1-9-MeA-N7)2{Pt(NH3)3)}2]6+ (3), stepwise migration of cis-(NH3)2PtII takes place in the alkaline aqueous solution to give initially cis-[(NH3)2Pt(N1-9-MeA-N7)(N6-9-MeA--N7){Pt(NH3)3}2]5+ (4) and eventually cis-[(NH3)2Pt(N6-9-MeA--N7)2{Pt(NH3)3}2]4+ (5) (with 9-MeA = neutral 9-methyladenine, 9-MeA- = 9-methyl-adenine monoanion, deprotonated at N6). The migration process has been studied by 1H NMR spectroscopy, and relevant acid-base equilibria have been determined. 5 has been crystallized as its nitrate salt and has been characterized by X-ray crystallography. The precursor of 3, [(NH3)3Pt (9-MeA-N7)]Cl2.2H2O (2) has likewise been studied by X-ray analysis. 相似文献
5.
N. S. Prostakov A. Ya. Ismailov V. P. Zvolinskii 《Chemistry of Heterocyclic Compounds》1973,9(7):907-910
The condensation of 3-methyl-2-azafluorene with esters of aromatic and aliphatic acids has given 9-aroyl and 9-acyl derivatives of 2-azafluorene. They are stable in the enolic form. The 9-benzoyl derivative (II) has also been isolated in the oxo form. The transition from (II) to the cis-trans isomers of 9-benzylidene-3-methyl-2-azafluorene has been effected.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 986–989, July, 1973. 相似文献
6.
Maxim V. Musalov Vladimir A. Potapov Svetlana V. Amosova 《Molecules (Basel, Switzerland)》2021,26(10)
The efficient synthesis of a new family of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonanes in high yields has been developed based on 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion generated from bis-isothiouronium salt of 2,6-dibromo-9-selenabicyclo[3.3.1]nonane. The derivatives of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonane containing alkyl, allyl and benzyl moieties have been prepared in 90–99% yields by nucleophilic substitution of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion with alkyl, allyl and benzyl halides. The reaction of nucleophilic addition of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion to alkyl propiolates afforded 2,6-di(vinylsulfanyl)-9-selenabicyclo[3.3.1]nonanes. The conditions for regio- and stereoselective addition of 9-selenabicyclo[3.3.1]nonane-2,6-dithiolate anion to a triple bond of alkyl propiolates have been found. To date, not a single representative of 2,6-disulfanyl-9-selenabicyclo[3.3.1]nonanes has been described in the literature. 相似文献
7.
Janusz B. Kyziol 《Journal of heterocyclic chemistry》1985,22(5):1301-1305
The synthesis of 3-nitrosocarbazole (I) by the Fischer-Hepp rearrangement of 9-nitrosocarbazole has been described. The resistance of I to oxidation provides evidence that it cannot be the intermediate in the conversion of 9-nitrosocarbazole to the C-nitro compounds. It has also been shown that I and its derivatives cannot be synthesized by the action nitrosyl chloride on carbazoles. Methylation of I yields 9-methyl-3-nitrosocarbazole, 9,9′-dimethyl-3-azocarbazole and 9,9′-dimethyl-3-azoxycarbazole as the main products. The mechanism of this disproportionation process has been proposed. The spectral data of I are given. 相似文献
8.
The synthesis of various substituted fluoren-9-ones has been accomplished by a novel palladium-catalyzed cyclocarbonylation of o-halobiaryls. The cyclocarbonylation of 4'-substituted-2-iodobiphenyls produces very high yields of 2-substituted fluoren-9-ones bearing either electron-donating or electron-withdrawing substituents. 3'-Substituted 2-iodobiphenyls afford in excellent yields with good regioselectivity 3-substituted fluoren-9-ones. This chemistry has been successfully extended to polycyclic and heterocyclic fluorenones. 相似文献
9.
A number of derivatives of peganine and vasicinone have been obtained: 4-hydroxy-9-O-methylpeganine, isodihydrovasicinone,
and 9-methoxy-, 9-phenoxy-, and 9,9-dichlorodeoxyvasicinones. An unusual ease of reduction of vasicinone and of 9-chlorodeoxyvasicinone
has been found. An introduction of a hydroxy group into position 4 of a dihydroquinazoline alkaloid with the aid of sodium
hydride has been detected.
Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh
Soedinenii, No. 4, pp. 541–545, July–August, 1991. 相似文献
10.
Bruce Coxon Alexander J. Fatiadi Alex Cohen Harry S. Hertz Robert Schaffer 《Magnetic resonance in chemistry : MRC》1980,13(3):187-192
A new monoxanthen‒9‒yl derivative of urea has been synthesized and the structure of this product (N‒9 H‒xanthen‒9‒ylurea) and that of the previously known N,N′‒di‒9 H‒xanthen‒9‒ylurea have been proved by 15N NMR and other spectroscopic techniques. A series of 13C and 15N labeled urea derivatives has been prepared and the utility of their 13C and 15N chemical shifts and coupling constants in the structural analysis of urea derivatives has been investigated. 相似文献
11.
12.
A number of derivatives of peganine and vasicinone have been obtained: 4-hydroxy-9-O-methylpeganine, isodihydrovasicinone, and 9-methoxy-, 9-phenoxy-, and 9,9-dichlorodeoxyvasicinones. An unusual ease of reduction of vasicinone and of 9-chlorodeoxyvasicinone has been found. An introduction of a hydroxy group into position 4 of a dihydroquinazoline alkaloid with the aid of sodium hydride has been detected.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 541–545, July–August, 1991. 相似文献
13.
Hiratsuka H Horiuchi H Furukawa Y Watanabe H Ishihara A Okutsu T Tobita S Yoshinaga T Shinohara A Tokitoh N Oba M Nishiyama K 《The journal of physical chemistry. A》2006,110(11):3868-3874
Photophysical and photochemical processes of 9-methyl- and 9-phenyl-9,10-dihydro-9-silaphenanthrene derivatives have been studied at room temperature and 77 K in comparison with the carbon analogue, 9,10-dihydrophenanthrene. These 9,10-dihydro-9-silaphenanthrene derivatives show smaller fluorescence quantum yield and remarkably larger Stokes shifts than those of the carbon analogue. In contrast, their phosphorescence quantum yields are two times larger than those of the carbon analogue, although the absolute value is not so large (approximately 0.1). Reaction products and intermediates produced by the 266 nm light photolysis have been studied, and it has been confirmed that 9-methyl- and 9-phenyl-9-silaphenanthrenes have been photochemically formed in methylcyclohexane at 77 K, in addition to the formation of radical cations of 9,10-dihydro-9-silaphenanthrene derivatives and the carbon-centered radical: 9-hydro-9-silaphenanthrenyl radical. 相似文献
14.
Mouna Ferchichi Erwann JeanneauBernard Fenet Faouzi MeganemUlrich Darbost Isabelle Bonnamour 《Tetrahedron letters》2012,53(32):4047-4050
The synthesis of a series of six new per-substituted p-tert-butylcalix[9]arenes derivatives has been achieved. Functions such as ester, nitrile, or carbonate have been grafted on the phenolic oxygens of calix[9]arene: p-tert-butylcalix[9]arene nona-ethyl acetate, p-tert-butylcalix[9]arene nona-carboxylic acid, p-tert-butylcalix[9]arene nona-cyanopropyloxy, p-tert-butylcalix[9]arene nona-tert-butoxycarbonyle, p-tert-butylcalix[9]arene nona-acetyl, and p-tert-butylcalix[9]arene nona-trifluoroacetyl have been obtained in good yields (from 48% to 78%) and fully characterized. The X-ray structures of p-tert-butylcalix[9]arene nona-tert-butoxycarbonyl and p-tert-butylcalix[9]arene nona-ethyl acetate have been determined. A dynamic NMR study has revealed the high conformational mobility of such structures, even at low temperature. 相似文献
15.
Anhydroerythromycin A arises from the acid-catalysed degradation of erythromycin A both in vitro and in vivo. It has negligible antibacterial activity, but inhibits drug oxidation in the liver, and is responsible for unwanted drug-drug interactions. Its structure has 18 chiral centres common with erythromycin A, but C-9 (the spiro carbon) is also chiral in anhydroerythromycin and its stereochemistry has not previously been reported; both 9R- and 9S-anhydroerythromycin A are plausible structures. An understanding of the chirality at C-9 was expected to throw light on the mechanism of acid-catalysed degradation of erythromycin A, a subject that has been debated in the literature over several decades.We now report a determination of the three-dimensional structure of anhydroerythromycin A, including the stereochemistry at C-9, by NMR and molecular modelling. In parallel, the relative stereochemistry of anhydroerythromycin A 2'-acetate was determined by X-ray crystallography. Both compounds were shown to have 9R stereochemistry, and anhydroerythromycin A exhibited considerable conformational flexibility in solution. 相似文献
16.
Grace E. Florence Katy A. Bruce Dr. Helena J. Shepherd Dr. William J. Gee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(41):9597-9601
A metastable form of 9-fluorenone (MS9F) has been characterized using Raman spectroscopy, fluorimetry, and X-ray diffraction techniques. MS9F emits blue fluorescence (λmax=495 nm) upon 365 nm irradiation and undergoes a single-crystal-to-single-crystal (SCSC) transformation to reach the ground state form (GS9F) over approximately 30 minutes, whereupon it emits the expected green fluorescence. A structure–property relationship for this fluorescent behavior has been posited. MS9F and GS9F were applied as a means of visualizing latent fingermarks on a nonporous surface. This approach identified three different modes of fluorescent fingermark visualization using 9-fluorenone. 相似文献
17.
The synthesis of various substituted fluoren-9-ones has been accomplished by the palladium-catalyzed cyclocarbonylation of o-halobiaryls. The cyclocarbonylation of 4'-substituted 2-iodobiphenyls produces very high yields of 2-substituted fluoren-9-ones bearing either electron-donating or electron-withdrawing substituents. 3'-Substituted 2-iodobiphenyls afford 3-substituted fluoren-9-ones in excellent yields with good regioselectivity. This chemistry has been successfully extended to polycyclic fluorenones and fluorenones containing fused isoquinoline, indole, pyrrole, thiophene, benzothiophene, and benzofuran rings. 相似文献
18.
Tylophorine has been degraded to a compound, identified as 2:3:6:7-tetramethoxy-9-methylphenanthrene. In conjunction with other degradation results and biogenetic considerations, tylophorine is now formulated as 2:3:6:7-tetramethoxyphenanthro(9:10:6′:7′)indolizidine.
A synthesis of the basic ring system, phenanthro-(9:10:6′:7′)indolizidine, present in tylophorine has been achieved. 相似文献
19.
Palladium catalyzed domino C-H functionalization reaction of arylaldehyde with dihaloarene has been developed to access 9-flourenone molecules. Bidentate ligand assisted strategy, single step reaction, high yield and excellent functional group tolerance make this method concise and effective for the synthesis of 9-flourenone. In addition, proposed method has been successfully employed to synthesise Tilorone in gram scale. 相似文献
20.
Yung Hsin Pan Roland K. Robins Leroy B. Townsend 《Journal of heterocyclic chemistry》1967,4(2):246-250
The preparation of 2, 6-dichloro-9-(2′,3′,4′-tri-O-acetyl-β-D-ribopyranosyl)purine (I) has been accomplished utilizing the acid catalyzed fusion procedure. The displacement of the 6-chloro group, or the 2- and 6-chloro group has been studied. Several new 6-substituted-9-(β-D-ribopyranosyl)purines have been prepared by catalytic dehalogenation of the corresponding 2-chloropurine nucleosides. The conformation and configuration of these D-ribopyranosylpurines has been assigned with the assistance of proton magnetic resonance studies. 相似文献