1,277 research outputs found
2-Chloro-N-(4-methoxyphenyl)benzamide
In the title compound, C14H12ClNO2, the chloro- and methoxy-substituted benzene rings are close to orthogonal [dihedral angle = 79.20 (3)°]. These rings also make angles of 45.9 (3) and 33.5 (3)° with the amide –CONH– unit. The methoxy substituent lies close to the methoxybenzene ring plane, with a maximum deviation of 0.142 (3) Å for the methyl C atom. The N—H bond is anti to the 2-chloro substituent of the aniline ring. In the crystal structure, intermolecular N—H⋯O hydrogen bonds form C(4) chains augmented by a weak C—H⋯O interaction involving an ortho H atom of the methoxy benzene ring that generates an R
2
1(6) motif. The chains stack the molecules into columns down the b axis. Adjacent columns are linked by additional C—H⋯O and C—H⋯π contacts, generating a three-dimensional network
Oral History of Glenn Presley
Written interview with Glenn Scott Presley, 1996 recipient of the Christa McAuliffe award.https://scholars.fhsu.edu/ors/1269/thumbnail.jp
2-[(N-Benzyl-4-methylbenzenesulfonamido)methyl]pyridinium nitrate
In the title compound, C20H21N2O2S+·NO3
−, the dihedral angle between the pyridinium and phenyl rings is 81.77 (19)°, that between the pyridinium and tolyl rings is 1.36 (18)°, and that between the phenyl and tolyl rings is 82.69 (19)°. In the crystal, the components are linked by strong charge-assisted bifurcated N+—H⋯(O,O) hydrogen bonds and the packing is consolidated by numerous weak C—H⋯O bonds and π–π stacking interactions [for the latter, centroid–centroid separation = 3.868 (2) Å]
(E)-4-Bromo-N-(2,4-dimethoxybenzylidene)aniline
The title Schiff base compound, C15H14BrNO2, adopts an E configuration with respect to the C=N bond. The C and O atoms of the two methoxy substituents lie very close to the dimethoxyphenyl ring plane [maximum deviation = 0.17 (1) Å]. The dihedral angle between the two aromatic rings is 43.69 (16)°, while the plane through the central C—C=N—C system is inclined at 10.6 (6)° to the dimethoxyphenyl ring and 34.6 (3)° to the bromophenyl ring. In the crystal structure, each molecule is involved in the formation of two inversion-related dimers through weak C—H⋯N and C—H⋯O interactions, respectively. These contacts link the molecules into independent rows parallel to the b axis
1-(2-Fluorophenyl)-6,7-dimethoxyisochroman
In the title compound, C17H17FO3, the benzene ring of the isochroman unit is inclined at 84.96 (7)° to the fluorobenzene ring plane, and the pyran ring adopts a half-boat conformation. In the crystal structure, C—H⋯O hydrogen bonds link molecules into rows along the c axis, while C—H⋯O interactions and C—H⋯F hydrogen bonds to the fluorine acceptor stack the molecules down the b axis. In addition, the crystal structure exhibits a weak C—H⋯π interaction between a methyl H atom of the methoxy group and the dimethoxybenzene ring of an adjacent molecule
Mutation of Arabidopsis SPLICEOSOMAL TIMEKEEPER LOCUS1 Causes Circadian Clock Defects
The circadian clock plays a crucial role in coordinating plant metabolic and physiological functions with predictable environmental variables, such as dusk and dawn, while also modulating responses to biotic and abiotic challenges. Much of the initial characterization of the circadian system has focused on transcriptional initiation, but it is now apparent that considerable regulation is exerted after this key regulatory step. Transcript processing, protein stability, and cofactor availability have all been reported to influence circadian rhythms in a variety of species. We used a genetic screen to identify a mutation within a putative RNA binding protein (SPLICEOSOMAL TIMEKEEPER LOCUS1 [STIPL1]) that induces a long circadian period phenotype under constant conditions. STIPL1 is a homolog of the spliceosomal proteins TFP11 (Homo sapiens) and Ntr1p (Saccharomyces cerevisiae) involved in spliceosome disassembly. Analysis of general and alternative splicing using a high-resolution RT-PCR system revealed that mutation of this protein causes less efficient splicing of most but not all of the introns analyzed. In particular, the altered accumulation of circadian-associated transcripts may contribute to the observed mutant phenotype. Interestingly, mutation of a close homolog of STIPL1, STIP-LIKE2, does not cause a circadian phenotype, which suggests divergence in function between these family members. Our work highlights the importance of posttranscriptional control within the clock mechanism. © 2012 American Society of Plant Biologists. All rights reserved
The gifts of the Roland: the old French Gui de Bourgogne
This piece explores the dialectical relation between the Old French epic, Gui de Bourgogne, and one of its key models, the Roland tradition. The tension between the two works is thematicised in the rivalry between the two generations of heroes: that of Roland and Olivier on the one hand and then a younger cohort of French warriors, led by Gui, who have grown up in the absence of their fathers. The essay examines how personal, social and economic interactions in the poem reflect an ambivalence partly reflective of a crippling sense of literary and historical debt to the giants of the epic tradition
The gifts of the Roland: the old French Gui de Bourgogne
This piece explores the dialectical relation between the Old French epic, Gui de Bourgogne, and one of its key models, the Roland tradition. The tension between the two works is thematicised in the rivalry between the two generations of heroes: that of Roland and Olivier on the one hand and then a younger cohort of French warriors, led by Gui, who have grown up in the absence of their fathers. The essay examines how personal, social and economic interactions in the poem reflect an ambivalence partly reflective of a crippling sense of literary and historical debt to the giants of the epic tradition
A monoclinic polymorph of N-(3-chlorophenyl)benzamide
The title compound, C13H10ClNO, (I), is a polymorph of the structure, (II), first reported by Gowda et al. [Acta Cryst. (2008), E64, o462]. In the original report, the compound crystallized in the orthorhombic space group Pbca (Z = 8), whereas the structure reported here is monoclinic P21/c (Z = 4). The principal difference between the two forms lies in the relative orientations of the phenyl and benzene rings [dihedral angle = 8.90 (13)° for (I) and 61.0 (1)° for (II)]. The inclination of the amide –CONH– units to the benzoyl ring is more similar [15.8 (7)° for (I) and 18.2 (2)° for (II)]. In both forms, the N—H bonds are anti to the 3-chloro substituents of the aniline rings. In the crystal, intermolecular N—H⋯O hydrogen bonds form C(4) chains along c. These chains are bolstered by weak C—H⋯O interactions that generate R
2
1(6) and R
2
1(7) ring motifs
Ethyl 5-hydroxy-6-oxo-4-phenyl-5,6-dihydro-4H-cyclopenta[b]thiophene-5-carboxylate
In the title molecule, C16H14O4S, the dihydrocyclopentathiophenone ring system is almost planar, with an r.m.s. deviation of 0.060 Å from the best fit plane through all nine non-H atoms. The cyclopentanone ring adopts a severely flattened envelope conformation with the C atom carrying the OH and ethylcarboxylate substituents at the flap. This atom lies only 0.185 (3) Å from the plane through the other four C atoms. The phenyl substituent is inclined at 43.37 (5)° to the dihydrocyclopentathiophenone mean plane. In the crystal, molecules are linked by pairs of O—H⋯O hydrogen bonds, forming inversion dimers with R
2
2(10) ring motifs. Weak C—H⋯O hydrogen bonds also link molecules into chains along c, while an approximately orthogonal set of C—H⋯O contacts form chains along b, resulting in layers lying parallel to (100). Inversion dimers also form through weaker R
2
2(12) C—H⋯S contacts, which combine with C—H⋯O contacts to form stacks along b
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