4-Azidomethyl-7-methyl-2-oxo-2H-chromene-6-sulfonyl azide

In the title compound, C11H8N6O4S, the plane of the coumarin aromatic ring is twisted by 17.2 (2)degrees with respect to the plane of the azide group bound to the methylene substituent, whereas it is twisted by 83.2 (2)degrees to the plane of the azide attached to the sulfonyl group. The crystal structure is stabilized by weak C-H center dot center dot center dot O interactions, leading to the formation of dimers with R-2(2)(12) graph-set motifs. These dimers are further linked by weak S-O center dot center dot center dot pi and pi-pi contacts centroid-centroid distance = 3.765 (2) angstrom], leading to the formation of a layered structure.

(2R,3R,4aS,6S,7S,8aS)-4a-Fluoro-8a-hydroxyperhydronaphthalene-2,3,6,7-te trayl tetraacetate

The title compound, C18H25FO9, exhibits a similar unit cell and packing to the alpha polymorph of axial 4a,8a-dihydroxyperhydronaphthalene-2,3,6,7-tetrayl tetraacetate. The carbonyl O atoms of two of the four acetate groups in the molecule are disordered over two sites with occupancy ratios of 0.59 (4):0.41 (4) and 0.57 (6):0.43 (6). Crystal packing is effected via intermolecular O-H center dot center dot center dot O hydrogen bonds, which link the tetraacetate molecules into tapes along the c axis.

Synthesis of (±)-thaps-7(15)-ene and (±)-thaps-6-enes

The synthesis of (±)-3a,4,4,7a-tetramethylhydrindan-2-one 8, containing three contiguous quaternary carbons as present in thapsanes, and the total synthesis of thaps-7(15)-ene 6 and thaps-6-ene 7, probable biogenetic precursors of thapsanes, have been achieved. Thus, orthoester Claisen rearrangement of cyclogeraniol 14, followed by hydrolysis of the resultant ester 16 furnished the eneacid 13. Copper sulfate-catalysed intramolecular cyclopropanation of the diazo ketone 18, derived from the acid 13, generated the cyclopropyl ketone 12. Regiospecific reductive cleavage of cyclopropyl ketone 12 furnished the hydrindanone 8, whereas the diazo ketone 26 furnished the hydrindanone 28avia the cyclopropyl ketone 27. Wittig methylenation of the hydrindanone 28a furnished thaps-7(15)-ene 6, which on isomerisation gave thaps-6-ene 7. Allylic oxidation of thaps-6-ene furnished the thapsenone 31, a degradation product of the natural thapsane 1b.

The unusual formation of methyl alpha-(5,6-dimethoxycarbonyl-2,3-dimethoxyazepin-7-ylidene)-alpha-[5-methoxycarbonyl-2,3-dimethoxypyrid-6-yl)acetate during the pyrolysis of ''azido-meta-hemipinate'' - First example of a reaction involving a concomitant ring expansion and ring extrusion

he ortho methoxycarbonyl substituent constitutes a sole exception in the ring closure reactions of ortho substituted aryl azides, as it provides no rate acceleration to this reaction. Pyrolysis of ''azido-meta-hemipinate'', an aryl azide containing such a substituent, led us to the title compound, a new azepinylidenepyridylacetic ester, whose structure has been established unambiguously by a single crystal X-ray diffraction study. This is the first report of a reaction involving both a ring expansion to an azaheptafulvalene and a ring extrusion to a pyridyl ring residue.

Structure of 7-ethylamino-6-methyl-4-trifluoromethylcoumarin

C13H12F3NO2, M(r) = 271.2, triclinic, P1BAR, a = 5.029 (2), b = 7.479 (2), c = 17.073 (5) angstrom, alpha = 97.98 (2), beta = 95.54 (3), gamma = 103.62 (3)-degrees, V = 612.4 (4) angstrom 3, Z = 2, D(m) = 1.463, D(x) = 1.471 g cm-3, lambda(Mo K-alpha) = 0.71069 angstrom, mu = 1.23 cm-1, F(000) = 280, T = 298 K, final R value is 0.041 for 2047 observed reflections with \F(omicron)\ greater-than-or-equal-to 6-sigma(\F(omicron)\). The N-C(sp2) bond length is 1.356 (2) angstrom. The N and C atoms of the ethylamino group deviate by < 0.15 angstrom from the plane of the aromatic ring. Short intramolecular contacts, C(3)...F(17) 2.668 (3) angstrom [H(3)...F(17) 2.39 (2) angstrom, C(3)-H(C3)...F(17) 98 (1)-degrees], C(5)...F(18) 3.074 (3) and C(5)...F(19) 3.077 (3) angstrom exist in the structure. The crystal structure is stabilized by intermolecular N-H...O hydrogen bonds with N(12)-H(N12) 0.79 (3), H(N12)...O(11)' 2.36 (3), N(12)...O(11)' (x - 1, y + 1, z) 3.105 (3) angstrom and N(12)-H(N12)...O(11)' 155 (2)-degrees.

ChemInform Abstract: Synthesis Based on Cyclohexadienes. Part 16. Synthesis of Methyl 2,7-Dimethyltricyclo (5.2.2.01,5)undec-5-ene-6-carboxylates

Synthesis of methyl 2, 7-dimethyltricyclo{5.2.2.0(1,5}undec-5-en-6-carboxylates, the tricyclic skeleton present in (+)-allo-cedrol (1) is described using the Diels-Alder strategy. Thus, Birch reduction of the aromatic acid 8 gives 5, the methyl ester of which is isomerised with DBU to a 1:1 mixture of the dienes 6 and 4. Cycloaddition of this mixture with 2-chloroacrylonitrile followed by hydrolysis yields the ketone 60 having the tricyclo{5.2.2.0(1.5)}undec-5-ene framework. Similar reaction with methyl vinyl ketone affords the regioisomeric adducts 61 and 62.

Structure of 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorodecyl 1,10-ditosylate by X-ray crystallography and F-19-NMR spectroscopy

2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluorodecyl 1,10-ditosylate and its precursors were synthesized and characterized by H-1- and F-19-NMR spectroscopic methods and X-ray crystallography. These compounds are building blocks for the syntheses of the surfactants containing polyperfluoromethylene spacer. The molecule has extended all-trans conformation with molecular symmetry (1) over bar (C-i). There is a reasonably strong C-H ... O interaction in the crystal and there are two F ... F intermolecular contact distances less than the sum of van der Waals radii. (C) 1999 Elsevier Science B.V. All rights reserved.

A comparison of the DNMR behaviour of methyl 5,6-bis(2-methoxyphenyl)-1,4-dimethyl-7-oxobicyclo[2.2.1]hept-5-en-2-endo-carboxylate and its 7-oxa analogue

Methyl 5,6-Bis(2-methoxyphenyt)-1,4-dimethyl-7-oxobicyclo[2.2.1]hept-5-en-2-endo-carboxylate, a moderately crowded norbornenone ester, exhibits complex VT-DNMR behaviour. A similar behaviour is not seen in its 7-oxa analogue, showing that conformational transmission from position 7 has a crucial influence on the distance parameters that govern the dynamic processes involving the substituents on the bicycloheptene framework.

Halogen Bonding and Chalcogen Bonding in 4,7-Dibromo-5, 6-dinitro-2,1,3-benzothiadiazole

An organic solid, 4,7-dibromo-5,6-dinitro-2,1,3-benzothiadiazole, has been designed to serve as an illustrative example to quantitatively evaluate the relative merits of halogen and chalcogen bonding in terms of charge density features. The compound displays two polymorphic modifications, one crystallizing in a non-centrosymmetric space group (Z' = 1) and the other in a centrosymmetric space group with two molecules in the asymmetric unit (Z' = 2). Topological analysis based on QTAIM clearly brings out the dominance of the chalcogen bond over the halogen bond along with an indication that halogen bonds are more directional compared to chalcogen bonds. The cohesive energies calculated with the absence of both strong and weak hydrogen bonds as well as stacking interaction are indicative of the stabilities associated with the polymorphic forms.

Letras, 1982-1983, nº 6-7 (número completo)

Contenido: Editorial – La personalidad del maestro Ángel J. Battistessa / Octavio N. Derisi – Soneto del cumpleaños, opus 80 / Ángel J. Battistesa – Plácemes, evocaciones y semblanzas – Una reelaboración estilística de Enrique Larreta / Arturo Berenguer Carisomo – Battistessa traductor de Dante / Eugenio Castelli – El problema de la lengua y otros aspectos americanistas en la obra de Andrés Bello / Graciela M. Pucciarelli de Colantonio – Góngora y la poesía pura / Celina Sabor de Cortazar – Maestros e ingratitudes / Elso Darío Di Bernardo – Cuatro clases de modificadores causales con “porque” / Ofelia Kovacci – Un Calisto o Romeo anónimo del siglo XVI / Rafael Lapesa – Lectura retórica de Facundo / Luisa López Grigera – Cautivos en la literatura argentina del siglo XX / Luis Martínez Cuitiño – Aproximaciones a Benito Lynch y su obra / María Luisa Montero – Nota a un cuento de Jorge Luis Borges / Eithel Orbit Negri – Ardientes hebras, do s’ilustra el oro / Germán Orduna – La escritura de Manuel Gálvez / Antonio Pagés Larraya – Ulises de Joyce: el laberinto y el secreto / Rosa E. M. D. Penna – La composición de las “figuras” en “El mundo por de dentro” / Melchora Romanos – Celos, aun del aire, matan (de Juan Hidalgo y Pedro Calderón de la Barca) en versión de nuestro tiempo / Beatriz Entenza de Solare – Doctrina metafísica tradicional del Romance de la Infantina Encantada / Aquilino Suárez Pallasá – La Sagrada Escritura en “Morada del cielo”, de Fray Luis de León / Teresa Herraiz de Tresca – Expresiones de agasajo y de recuerdo – Homenaje universitario y académico – En la perspectiva del tiempo

Simpatía y conducta prosocial en niños de 6 y 7 años

Resumen: El presente estudio analiza el rol de la simpatía en la conducta prosocial infantil, determinando posibles diferencias en función del sexo y la edad. La muestra estuvo constituida por 275 niños de ambos sexos, escolarizados, de 6 y 7 años de edad de las provincias de Chaco y Corrientes, Argentina. Previo consentimiento informado de los padres, se administró la Escala de simpatía para niños de 6 y 7 años de edad, de Oros (2006), el Prosocial BehaviorScale de Caprara y Pastorelli (1993) traducido y adaptado al español por Del Barrio, Moreno y López, (2001), y el Cuestionario de Conducta Prosocial (PBQ) de Weiner y Duveen (1981).En función de los objetivos propuestos, se realizó un análisis univariado de varianza (ANOVA) y análisis multivariados de variancia (MANOVAs). Los diferentes resultados obtenidos, se discuten en función de los desarrollos teóricos y empíricos encontrados hasta el momento, hallando una consistencia general entre los mismos

Descripção dos emblemas allegoricos, e seus epigramas, com que se adornou a illuminação que na fachada das cazas de sua residencia apresentou ao publico o coronel Antonio José da Silva Braga, na noute de 6 de fevereiro de 1818, em que se celebrou com pompa verdadeiramente real a feliz, e gloriosa acclamação do muito alto, e poderoso Rei Nosso Senhor D. João Sexto, e nas tres noites seguintes dos dias 7, 8, e 9 em memoria do seu reconhecimento, amor, e lealdade, que professa ao mesmo Augusto senhor, cuja preciosa vida os ceos dilatem por longos annos para gloria e delicia de toda a naçam portugueza

Coleção Marcio Moreira Alves.