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Ring Fused (ring + fused)
Selected Abstracts2-Trifluoroacetyl-1-methoxycycloalkenes: A convenient precursor for the synthesis of geminated polymethylene trifluoromethyl substituted heterocyclesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2009Helio Gauze Bonacorso This article describes the methodology that allows the simultaneous introduction of a trifluoromethyl group and a 7-, 8-, and 10-membered cycloalkane ring fused to heterocyclic derivatives. A series of 10 geminated polymethylene trifluoromethyl substituted isoxazolines, pyrazoles, pyrimidinones, and a pyrazolyl-quinoline were obtained in moderate to good yields from the reaction of three 2-trifluoroacetyl-1-methoxycycloalkenes derived from cycloheptanone, cyclooctanone, and cyclododecanone with hydroxylamine hydrochloride, hydrazine hydrochloride, urea, and 7-chloro-4-hydrazinoquinoline. J. Heterocyclic Chem., (2009). [source] 3,,4,-Bis(4-chlorophenyl)spiro[chroman-3,5,(4,H)-isoxazol]-4-oneACTA CRYSTALLOGRAPHICA SECTION C, Issue 4 2001A. Abdul Ajees The title compound, C23H15Cl2NO3, crystallizes with two independent molecules in the asymmetric unit. The chromanone moiety consists of a benzene ring fused with a six-membered heterocyclic ring which adopts a sofa conformation. The five-membered spiroisoxazoline ring is in an envelope conformation. The p -chlorophenyl rings bridged by the five-membered ring are nearly perpendicular to each other. The chromanone moiety of one molecule packs into the cavity formed by the p -chlorophenyl rings of a second molecule through the formation of C,H,, interactions. The structure is stabilized by weak C,H,O, C,H,Cl and C,H,, interactions. [source] 6-Dimethoxymethyl-1-methoxycarbonylbicyclo[3.1.0]hex-2-ene-2-carboxylic acidACTA CRYSTALLOGRAPHICA SECTION C, Issue 7 2000Satomi Niwayama The title compound, C12H16O6, prepared by a standard synthetic method, was determined by single-crystal X-ray crystallography to exist with a cyclopropane ring fused to a cyclopentene ring. Comparison of the unit-cell dimensions and space group of this material with those of a crystal of the same material prepared using a route involving pig liver esterase hydrolysis shows them to be identical. [source] Novel Fused Pyrrole Heterocyclic Ring Systems as Structure Analogs of LE 300: Synthesis and Pharmacological Evaluation as Serotonin 5-HT2A, Dopamine and Histamine H1 Receptor LigandsARCHIV DER PHARMAZIE, Issue 2 2010Sherif A. F. Rostom Abstract LE 300 represents a structurally novel type of antagonists acting preferentially at the dopamine D1/D5 receptors and the serotonin 5-HT2A receptor. This compound consists of a ten-membered central azecine ring fused to an indole ring on one side and a benzene moiety on the other side. To estimate the importance of the indole and / or phenyl moieties in this highly active benz-indolo-azecine, both rings were removed and replaced with a 1H -pyrrole counterpart. Accordingly, some new analogs of LE 300 namely, pyrrolo[2,3- g]indolizine, pyrrolo[3,2- a]quinolizine rings and their corresponding dimethylpyrrolo[2,3- d]azonine, and dimethylpyrrolo[2,3- d]azecine were synthesized to be evaluated for their activity at the 5-HT2A and dopamine D1, D2L, D4, D5 receptors in relation to LE 300. In addition, their activity at the H1 -histamine receptors was also determined. The results suggested that the rigid pyrrolo[2,3- g]indolizine 7 and pyrrolo[3,2- a]quinolizine 8 analogs lacked biological activity in the adopted three bioassays. However, their corresponding flexible pyrrolo[2,3- d]azonine 11 and pyrrolo[2,3- d]azecine 12 derivatives revealed weak partial agonistic activity and weak antagonistic potency at the serotonin 5-HT2A and histamine H1 receptors, respectively. Meanwhile, they showed no affinity to any of the four utilized dopamine receptors. Variation in ring size did not contribute to a significant influence on the three tested bioactivities. Removal of the hydrophobic moiety (phenyl ring) and replacement of the indole moiety with a 1H -pyrrole counterpart led to a dramatic alteration in the profile of activity of such azecine-type compounds. [source] Spirocycle (SitBu3)6Si9Cl2: The First of Its Kind among Group 14 Elements,EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2010Thomas M Klapötke Abstract Structural studies on (R*3Si4)2SiCl2, prepared by the reaction of tetrasilatetrahedranide KR*3Si4 with SiCl4, show that the tetrahedral moieties R*3Si4 undergo structural transformation. The molecule exhibits a spiro[4.4]nonasilane network that comprises two homonuclear tricyclo[2.1.0.02,5]pentasilane rings with a common "naked" silicon bridge. The compound shows structural similarities with R*6Si8, which consists of similar rings fused together along an Si,Si bridge. Comparison of valence angles, interplanar angles and bridgehead distances with respect to tricyclo[2.1.0.02,5]pentanes or similar ring systems with heteronuclear group homologues are reported to highlight the influence of bulky supersilyl R* groups in the structure. [source] | ||||||||||