In the title compound, C20H17NO3 (alternative name: N-hy-droxy-9,10-dimethyl-9,10-ethano-anthracene-11,12-dicarboximide), the rigid ethano-anthracene-dicarboximide moiety has a roof-shaped geometry, the inter-planar angle between the two terminal phenyl rings being 124.9 (6)°. In the crystal, mol-ecules are linked via O-H⋯O hydrogen bonds, forming chains along [010]. C-H⋯O and C-H⋯π inter-actio...

By providing a general correspondence between Landau-Ginzburg orbifolds and nonlinear sigma models, we find that the elusive mirror of a rigid manifold is actually a supermanifold. We also discuss when sigma models with super-target spaces are conformally invariant and describe their chiral rings. Both supermanifolds with and without Kähler moduli are considered. This work leads us to conclude ...

Crystallization-induced diastereoselective transformation (CIDT) of an α-methyl nitrile completes an entirely non-chromatographic synthesis of the halichondrin B C14-C26 stereochemical array. The requisite α-methyl nitrile substrate is derived from D-quinic acid through a series of substrate-controlled stereoselective reactions via a number of crystalline intermediates that benefit from a rigid...

We continue the study on equilibria of the Smoluchowski equation for dilute solutions of rigid extended (dipolar) nematics and dispersions under an imposed electric or magnetic field [25]. We first provide an alternative proof for the theorem that all equilibria are dipolar with the polarity vector parallel to the external field direction if the strength of the permanent dipole (μ) is larger th...

The proteasome is a multimeric and multicatalytic intracellular protease responsible for the degradation of proteins involved in cell cycle control, various signaling processes, antigen presentation, and control of protein synthesis. The central catalytic complex of the proteasome is called the 20S core particle. The majority of these are flanked on one or both sides by regulatory units. Most c...

A rigid-flexible manipulator may be assigned tasks in a moving environment where the winds or vibrations affect the position and/or orientation of surface of operation. Consequently, losses of the contact and perhaps degradation of the performance may occur as references are changed. When the environment is moving, knowledge of the angle α between the contact surface and the horizontal is requi...

Synthesis, spectral and structural characterization of a pyrroloindolizine derivative having structural similarity with calix[2]pyrrole is described. Here, two pyrrole rings are connected with two meso-carbon atoms having an N,α-linkage and an α,β-linkage to afford the smallest analogue in the calixpyrrole family. Detailed NMR spectroscopic studies along with single crystal X-ray analysis confi...

The asymmetric unit of the title compound, C26H28O6·2CH3OH, contains two independent methyl 6-O-trityl-α-d-gluco-pyran-oside mol-ecules and four methanol solvent mol-ecules. The rings of two methyl α-d-gluco-pyran-oside adopt chair conformations. In the crystal, extensive intra- and inter-molecular O-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules into a three-dimensional supra-molecular archi...

The title compound, C(21)H(23)NO(3), is a phenyl-imine derivative of the well known anthelmintic agent α-santonin. The trans-fused cyclo-hexane and γ-lactone rings of the α-santonin ring system adopt chair and envelope conformations, respectively, whereas the hexa-diene ring is approximately planar [maximum deviation = 0.029 (4) Å] and forms a dihedral angle of 62.30 (11)° with the benzene ring...

We define the notions of finite-state and functionally recursive matrices and their growth. We also introduce two rings generated by functionally recursive matrices. The first is isomorphic to the 2-generated free ring. The second is a 2-generated monomial ring such that the multiplicative semigroup of monomials in the generators is nil of degree 5 and the ring has Gelfand Kirillov dimension 1 ...