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排序方式: 共有248条查询结果,搜索用时 218 毫秒
61.
M. J. Musmar Gary E. Martin Robert T. Gampe Milton L. Lee Ralph E. Hurd Marvin L. Tedjamulia Hirotaka Kudo Raymond N. Castle 《Journal of heterocyclic chemistry》1985,22(1):219-223
Total assignment of the 13C-nmr spectrum of the helical molecule phenanthro[4,3-a]dibenzothiophene at 125.762 MHz is reported. Assignments were made by the combined application of 13C-13C autocorrelated double quantum coherence and heteronuclear relayed coherence transfer (RELAY) experiments. 相似文献
62.
Aileen Pfleider Halverson Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1996,33(1):179-183
Naphtho[1′,2′:4,5]thieno[2,3-c][1,10]phenanthroline and naphtho[2′,1′:4,5]thieno[2,3-c][1,10]phenanthroline, two novel polycyclic heterocyclic ring systems, have been synthesized in four steps from known starting materials. The total 1H nmr spectral assignments were made using a COSY experiment to identify the spin systems. 相似文献
63.
Aileen Pfleider Halverson Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1996,33(1):119-122
The synthesis of thieno[2′,3′:4,5]thieno[2,3-c][1,10]phenanthroline ( 5 ) and thieno[3′,2′:4,5]thieno-[2,3-c][1,10]phenanthroline ( 10 ) are described. Each compound was obtained in four steps from known starting materials. The basic skeleton of the molecule and of the phenanthroline ring were formed via photocyclization. The total assignment of 1H-nmr spectra was accomplished with the aid of two-dimensional nmr methods. 相似文献
64.
J. C. Kuei J. I. Shelton L. W. Castle R. C. Kong B. E. Richter J. S. Bradshaw M. L. Lee 《Journal of separation science》1984,7(1):13-18
A crosslinkable biphenylmethylpolysiloxane stationary phase was synthesized for capillary column gas chromatography and compared with methyl, phenyl, and cyanopropyl polysiloxane stationary phases for the separation of isomeric polycyclic aromatic compounds. While the new phase gave similar separations of nonpolar isomers when compared to the nonpolar phases, separations of polar isomers were greatly improved because of the induced polarity of the biphenyl group of the stationary phase by the solute molecules. This polarizable stationary phase offers a unique selectivity which is not available in other stationary phases. 相似文献
65.
Yoshinori Tominaga Raymond N. Castle Milton L. Lee 《Journal of heterocyclic chemistry》1982,19(5):1125-1130
Two pentacyclic thiophenes, benzo[4,5]phenaleno[1,9–6c]thiophene ( 1 ) and benzo[4,5]phenaleno[9,1-bc]-thiophene (2) were synthesized via the corresponding 3-methylphenanthro[2,1-b]thiophene (7) and 1-methylanthra[2,1–6]thiphene ( 19 ). 相似文献
66.
Ram Pratap Yoshinori Tominaga Milton L. Lee Raymond N. Castle 《Journal of heterocyclic chemistry》1981,18(5):973-975
The synthesis of all the isomers of pyreno[b]thiophene namely, pyreno[1,2-b]thiophene, pyreno[2,1-b]thiophene and pyreno[4,5-b]thiophene is described. Their spectral characteristics are also discussed. 相似文献
67.
Yoshinori Tominaga Milton L. Lee Raymond N. Castle 《Journal of heterocyclic chemistry》1981,18(5):967-972
All isomers of the parent anthra[b]thiophenes and benzo[b]naphtho[d]thiophenes, namely anthra[2,3-b]thio-phene, anthra[2,1-b]thiophene, anthra[1,2-b]thiophene, benzo[b]naphtho[2,3-d]thiophene, benzo[b]naphtho[2,1-d]thiophene and benzo[b]naphtho[1,2-d]thiophene were synthesized using a new procedure. 相似文献
68.
Jiann-Kuan Luo Ronald F. Federspiel Raymond N. Castle 《Journal of heterocyclic chemistry》1997,34(5):1597-1601
Photocyclization of 3-chloro-N-(3-phenanthryl)thieno[2,3-b]thiophene-2-carboxamide ( 5 ) yielded only one of the two possible structural isomers, thieno[3′,2′:4,5]thieno[2,3-c]naphtho[1,2-f]quinolin-6(5H)-one ( 6 ), which was further elaborated to afford the unsubstituted ring system 10 , its triazole 11 and tetrazole 12 . The structural confirmation of 10 was achieved by the total assignment of its 1H and 13C nmr spectra by the concerted utilization of two-dimensional nmr spectroscopic methods. 相似文献
69.
Yoshinori Tominaga Lyle W. Castle Raymond N. Castle 《Journal of heterocyclic chemistry》1996,33(4):1319-1321
Photocyclization of the substituted 2-([1]benzothien-3-yl)-3-phenylpropenoic acids 3a-c in the presence of iodine and air in a benzene-cyclohexane mixture afforded a separable mixture of three compounds, benzo[b]naphtho[2,1-d]thiophene-6-carboxylic acids 4a-c , 6H-benzo[b]naphtho[2,3-d]thiopyran-6-ones 5a-c , and 10-methoxy-2-methyl-6H-benzo[b]naphtho[2,3-d]pyran-6-one ( 6 ). 相似文献
70.
The synthesis of both isomers of benzo[1,2]phenaleno[bc]thiophene namely, benzo[1,2]phenaleno[3,4-bc]-thiophene and benzo[1,2]phenaleno[4,3-bc]thiophene is described. 相似文献