Electronic effects on C-O-C ether bonds in 3-aryloxy derivatives of benzisothiazole 1,1-dioxides: rapid ethanolysis of 3-(4-nitrophenoxy)-1,2-benzisothiazole 1,1-dioxide, (1), to give 3-ethoxy-1,2-benzisothiazole 1,1-dioxide, (2)

The bond lengths in the central C-O-C ether linkage of title compound (1), C13H8N2O5S, are comparable with those found in earlier work on similar compounds. However, (1) was found to undergo very easy solvolysis with ethanol to give (2), C9H9NO3S, for which a structure was also determined, but 3-(4-methoxyphenoxy)-1,2-benzisothiazole 1,1-dioxide, (3), did not hydrolyse under the same conditions. If ground-state structures are important for solvolysis, these results suggest that there should be a difference in the corresponding C-O bond lengths for the ethers (1) and (3). Such differences are not observed. The results can be rationalized by supposing that transition-state energies for ethanolysis are more important factors than those of the ground state.info:eu-repo/semantics/publishedVersio

Thermal rearrangement of 3-allyloxy-1,2-benzisothiazole 1,1-dioxides: an unusual inversion of products of sigmatropic [3,3]-shift to give the [1,3]-Isomers

3-Allyloxy-1,2-benzisothiazole 1,1-dioxides isomerize thermally to give [3,3]- and [1,3]-products 6 of sigmatropic shift, of which the former reacts further to give solely the [1,3]-isomer

The global mass function of M15

Data obtained with the NICMOS instrument on board the Hubble Space Telescope (HST) have been used to determine the H-band luminosity function (LF) and mass function (MF) of three stellar fields in the globular cluster M15, located ~7' from the cluster centre. The data confirm that the cluster MF has a characteristic mass of ~0.3 Msolar, as obtained by Paresce & De Marchi (2000) for a stellar field at 4.6' from the centre. By combining the present data with those published by other authors for various radial distances (near the centre, at 20" and at 4.6'), we have studied the radial variation of the LF due to the effects of mass segregation and derived the global mass function (GMF) using the Michie-King approach. The model that simultaneously best fits the LF at various locations, the surface brightness profile and the velocity dispersion profile suggests that the GMF should resemble a segmented power-law with the following indices: x ~ 0.8 for stars more massive than 0.8 Msolar, x ~ 0.9 for 0.3 - 0.8 Msolar and x ~ -2.2 at smaller masses (Salpeter's IMF would have x=1.35). The best fitting model also suggests that the cluster mass is ~5.4 10^5 Msolar and that the mass-to-light ratio is on average M/L_V ~ 2.1, with M/L_V ~ 3.7 in the core. A large amount of mass (~ 44 %) is found in the cluster core in the form of stellar heavy remnants, which may be sufficient to explain the mass segregation in M15 without invoking the presence of an intermediate-mass black hole.Comment: 12 pages, 10 figures, accepted for publication in A&

Estudos Luso-Hispanos de História do Direito

El primer volumen de los Estudios Luso-Hispanos de Historia del Derecho/ Estudos Luso-Hispanos de História do Direito recoge los trabajos presentados en el ámbito de la segunda edición del EHLHD (Encuentro Hispano-Luso de Historiadores del Derecho/Encontro Hispano-Luso de Historiadores do Direito), celebrado los días 6, 7 y 8 de julio de 2017 en la Universidad Autónoma de Madrid.Presentación / Laura Beck Varela y María Julia Solla Sastre (pp. 9-12). -- Quando il diritto era ancora compatto. Perché la storia giuridica svizzera è così diversa? / Pio Caroni (pp. 13-43). -- El derecho municipal medieval de la Cataluña Nueva (siglos XIII-XVII) / Josep Serrano Daura (pp. 45-62). -- Algunas consideraciones sobre el régimen local cantábrico frente al fomento naval y forestal en la Corona de Castilla (c.1560-1570) / Alfredo José Martínez González (pp. 63-91). -- Organização judiciária e administração da justiça no Portugal filipino: a “reformaçam da justiça” de Filipe I de Portugal (1582) / Jorge Veiga Testos (pp. 93-121). -- El oficio de secretario en la doctrina jurídica de la Edad Moderna / Marina Rojo Gallego-Burín (pp. 123-149). -- Notas sobre la reforma municipal carolina en Sevilla: la representación del común / María del Mar Tizón Ferrer (pp. 151-165). -- Un programa ilustrado para la formación de juristas. El Plan de Estudios de Pablo de Olavide de 1768 / Fernando Liendo Tagle (pp. 167-198). -- La formación del jurista en el virreinato del Perú en las postrimerías del antiguo régimen / Carlos Tormo Camallonga (pp. 199-237). -- Propiedad moderna y alteridad indígena en Brasil (1755-1862) / Camilla de Freitas Macedo (pp. 239-270). -- Direito, política e sociedade: as Novas Conquistas de Goa durante o Perismo. Os contributos de Nery Xavier e Cláudio Lagrange / Luís Pedroso de Lima Cabral de Oliveira y João Pedro Caleira (pp. 271-303). -- Horizonte nacional, espacio tradicional. La construcción jurídica de la nación y el extranjero en la constitución de Cádiz / Iván Pastoriza Martínez (pp. 305-337). -- La disolución de los consejos: entre quiebras, confusiones y continuidad (1834-1836) / Antonio Manuel Luque Reina (pp. 339-371). -- Justicia legal y derecho judicial: la influencia de la jurisprudencia en la formación de la ciencia jurídica isabelina / Blanca Sáenz de Santa María Gómez-Mampaso (pp. 373-409). -- Nuevas etiquetas disciplinares y sus contiendas: las ciencias políticas ante el derecho en Francia (1871-1900) / Pedro Luis López Herráiz (pp. 411-449). -- O casamento na legislação de 1910 em Portugal. A mudança de paradigma nas relações familiares / Miriam Afonso Brigas (pp. 451-479). -- Primeira Lei do Contrato de Trabalho em Portugal: Lei nº 1.952, de 10 de Março de 1937 / Margarida Seixas (pp. 481-513). -- A Revisão Constitucional de 1971: o Projecto de Lei 6/X da “Ala Liberal” num contexto de tensões internas no Marcelismo / Filipe de Arede Nunes (pp. 515-543)

[4+2] Cycloadditions of 3-Tetrazolyl-1,2-diaza-1,3-butadienes: synthesis of 3-Tetrazolyl-1,4,5,6-tetrahydropyridazines

The synthesis of new 3-tetrazolyl-1,4,5,6-tetrahydropyridazines by Diels–Alder reactions of ethyl 3-(tetrazol-5-yl)-1,2- diaza-1,3-butadiene-1-carboxylates is reported. These 1,2- diaza-1,3-dienes reacted with electron-rich heterocycles, nucleophilic olefins and cumulenes, as well as with electrondeficient dienophiles, to give the target compounds regioselectively. Computational studies corroborated the rationalization of the observed reactivity and selectivity

Structural effects on sigmatropic shifts in heteroaromatic allyl ethersElectronic supplementary information (ESI) available: selected crystal data for compound 7. See http://www.rsc.org/suppdata/p1/b1/b102674g/

In contrast to the known thermal, exclusively [3,3], O- to N- rearrangement of allyl groups in phenyltetrazoles (1, Scheme 1), the comparable migration of the allyl group in pseudosaccharyl ethers (3; Scheme 2) has been shown to proceed through both [1,3]- and [3,3]-mechanisms, 4, 5; for the pseudosaccharyl derivative of the natural product myrtenol (6; Scheme 3) only the product 7 of a [1,3]-shift has been observed; crystallographic data and theoretical calculations provide an explanation of this ease of [1,3]-isomerization and the observed selectivity as being due to conformational constraints and electronic factors