Diethyl 2,2′-(1,4-phenylenedioxy)diacetate

Julian Sorell Huxley 22 June 1887- 14 February 1975.

# a 22 Integers 14 ( 2014 ) a Density Chinese Remainder Theorem

Given collections A and B of residue classes modulo m and n, respectively, we investigate conditions on A and B that ensure that, for at least some (a, b) 2 A⇥B, the system: x ⌘ a mod m and x ⌘ b mod n has an integer solution, and we quantify the number of such admissible pairs (a, b). The special case where A and B consist of intervals of residue classes has application to the Lonely Runner Co...

12β,14-Dihy­droxy-3-oxo-5β,20(22)-cardenolide monohydrate

The title compound, digoxigenone, C(23)H(30)O(5)·H(2)O, was biotransformed from digoxigenin. In the crystal, inter-molecular O-H⋯O hydrogen bonds contribute to the formation of a three-dimensional supra-molecular structure. The title compound has three fused six-membered rings (A,B,C) and two non-fused five-membered rings (D,E). As in other structures, compound nucleus has a cis-trans-cis confo...

Hyperconjugation in diethyl ether cation versus diethyl sulfide cation.

Ionization of a molecule can greatly alter its electronic structure as well as its geometric structure. In this collaborative experimental and theoretical study, we examined variance in hyperconjugation upon ionization of diethyl ether (DEE) and diethyl sulfide (DES). We obtained the experimental gas phase vibrational spectra of DEE, DES, DEE(+), DES(+), DEE(+)-Ar, and DES(+)-Ar in the wavenumb...

Diethyl pyrazine-2,5-dicarboxyl­ate

The mol-ecule of the title compound, C(10)H(12)N(2)O(4), is located around an inversion center. The carboxyl-ate groups are twisted slightly with respect to the pyrazine ring, making a dihedral angle of 2.76 (19)°. In the crystal, mol-ecules are stacked along the c axis via weak C-H⋯O hydrogen bonds.