نتایج جستجو برای: aza crown ether
تعداد نتایج: 44147 فیلتر نتایج به سال:
The title thia-calix[4]arene derivative, C(36)H(34)Br(2)O(8)S(4), adopts an unusual pinched cone conformation with the prop-oxy-substituted benzene rings inclined inward [forming a dihedral angle of 33.4 (1)°] and with the brominated benzene rings bent outward, making a dihedral angle of 66.1 (1)°. In the crystal, the mol-ecules form chains along [001] via C-H⋯S hydrogen bonds and S⋯S contacts ...
The title compounds, 6-(2-hy-droxy-benz-yl)-5H-thia-zolo[3,2-a]pyrimidin-5-one, C13H8N2O3S, (1), and 6-(2-hy-droxy-benz-yl)-3-methyl-5H-thia-zolo[3,2-a]pyrimidin-5-one, C14H10N2O3S, (2), were synthesized when a chromone-3-carb-oxy-lic acid, activated with (benzotriazol-1-yl-oxy)tripyrrolidinyl-phospho-nium hexa-fluorido-phosphate (PyBOP), was reacted with a primary heteromamine. Instead of the ...
The asymmetric unit of the title compound, C(10)H(9)NO(5)S, contains two independent mol-ecules. The heterocyclic thia-zine rings in both mol-ecules adopt half-chair conformations, with the S atoms in each mol-ecule displaced by 0.455 (3) and 0.539 (3) Å and the N atoms displaced in the opposite direction by 0.214 (3) and 0.203 (3) Å, from the planes defined by the remaining ring atoms. The cry...
The title compound, C(15)H(8)Cl(2)N(2)O(2)S, crystallizes with two mol-ecules in the asymmetric unit. The dihedral angles between the 4-chloro-3-nitro-phenyl ring and the thia-zole ring are 0.5 (1) and 7.1 (1)° and those between the 4-chloro-phenyl ring and the thia-zole ring are 7.1 (1) and 7.4 (1)° in the two mol-ecules. The crystal structure is stabilized by inter-molecular C-H⋯Cl and C-H⋯O ...
The title compound, C16H13N3OS, comprises an oxa-diazo-lethione ring bound to the N atom of an almost planar carbazole ring system (r.m.s. deviation = 0.0088 Å) through an ethyl-ene chain. The oxa-diazole ring is inclined to the the carbazole ring system by 40.71 (6)°. In the crystal, N-H⋯O, N-H⋯S, C-H⋯N and C-H⋯S hydrogen bonds combine with C-H⋯π(ring) and π-π contacts to stack the mol-ecules ...
In the title compound, C(10)H(9)N(3)O(2)S(2), the dihedral angle between the benzene and thia-zolidine rings is 79.8 (2)°. Inter-molecular C-H⋯N and C-H⋯O inter-actions help to stabilize the crystal structure.
In the title compound, C(10)H(11)N(3)O(2)S, the thia-zine ring exists in a conformation inter-mediate between twist-boat and half-chair. The dihedral angle between the mean plane of the thia-zine ring and the hydrazide group is 89.45 (13)°. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into (100) sheets and weak C-H⋯O inter-actions further consolidate the packing.
In the title compound, C(11)H(8)BrN(3)OS, the dihedral angle between the benzene and thia-zolidine rings is 63.4 (2)°. Inter-molecular C-H⋯N inter-actions help to stabilize the crystal structure.
Nitrobenzofurazan derivatives are well known for their fluorescence, whilst crown ethers complexing capacity toward cationic species. In this study, we present the synthesis and structural characterization of a new derivative containing both nitrobenzofurazan moieties ether core. The compound was obtained from dibenzo-18-crown-6 ether, which first nitrated, reduced to corresponding amine, subse...
Two procedures for the synthesis of benzo-21-crown-7 have been explored. The [1+1] macrocyclization with KBF₄ as the template was found to be more efficient than the intramolecular macrocyclization without template. Pseudorotaxanes form with secondary ammonium ions bearing at least one alkyl chain narrow enough to slip into the crown ether. Substitution on benzo-21-crown-7 or on the secondary a...
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