The crystal structure of the title compound, [Sn4(C4H9)8(C17H12NO4)4O2], is composed of centrosymmetric dimers lying about inversion centers. Its central Sn2O2 core is fused, with two four‐membered (Sn2O2) and two six‐membered (Sn2O3C) rings, incorporating O and C atoms of N‐phthaloyl­phenyl­alaninate ligands that show different modes of coordination with tin. The endocyclic Sn atoms of the Sn2O2 core are six‐coordinate in a skew‐trapezoidal bipyramidal environment, while the exocyclic Sn atoms are essentially five‐coordinate and exhibit distorted trigonal–bipyramidal geometry. The Sn—C distances lie in a narrow range 2.117 (3)–2.137 (5) Å [mean 2.128 (7) Å]. The endocyclic Sn—O distances in the Sn2O2 core are 2.057 (3) and 2.157 (3) Å, while the exocyclic Sn—O distances [2.277 (3) and 2.725 (3) Å] indicate a strong and a relatively weak Sn⋯O interaction. The Sn—O distances involving the exocyclic Sn atom are in the range 2.031 (3)–2.232 (3) Å.

Key indicatorsSingle-crystal X-ray study T = 170 K Mean '(C±C) = 0.007 A Ê Disorder in main residue R factor = 0.050 wR factor = 0.148 Data-to-parameter ratio = 16.3For details of how these key indicators were automatically derived from the article, see

Piceatannol is a naturally occurring bioactive stilbene with documented antileukemic properties. It has been extensively used as a Syk-selective protein tyrosine kinase inhibitor for the study of various signaling pathways. Herein, we show that the hydroxystilbene, piceatannol, and related catechol ring-containing compounds are able to induce the loss of the Cbl family of proteins. Normal cellular Cbl-regulatory mechanisms were not involved in this process. Screening of a small library of piceatannollike compounds indicated that aromaticity and a catechol ring were required for the induction of Cbl loss. Further examination of these two chemical properties showed that the oxidative conversion of the catechol ring of piceatannol into a highly reactive O-benzoquinone was the cause of piceatannol-induced Cbl loss. Characterization of the Cbl selectivity of piceatannol-induced protein loss revealed that this compound was also able to induce the functional loss of specific Cbl-associated proteins involved in signaling pathways commonly associated with cancer. This work uncovers a new, piceatannol-dependent effect and shows a novel way in which this phenomenon can be exploited to inhibit disease-associated signaling pathways.

The central Ge atoms in the structures of 3-(2-fluorophenyl)-3-(triphenylgermyl)propionic acid, [Ge(C(6)H(5))(3)(C(9)H(8)FO(2))], 3-(2-tolyl)-3-(tri-4-tolylgermyl)propionic acid, [Ge(C(7)H(7))(3)(C(10)H(11)O(2))], and 3-(4-tolyl)-3-(tribenzylgermyl)propionic acid, [Ge(C(7)H(7))(3)(C(10)H(11)O(2))], are four-coordinate with slightly distorted tetrahedral geometry. The Ge-Csp(3) distances [1.970 (3)-1.997 (3) A] are significantly longer than the Ge-C(aromatic) distances [1.940 (3)-1.959 (2) A]. In all three structures, the molecules form dimeric pairs about inversion centres through strong hydrogen-bonding interactions between carboxylic acid groups.

In the course of systematic structural studies of dicitratoborates the investigation of the crystal structure of NH2CSHNH2[(C6H6O7)2B] has been carried out. The dicitratoborate complex with thiourea (L) was synthesized according to [1]. The structure is formed by cations of thiourea (HL) + and spiran-type complex anions [(C6H6O7)2B] -. In the complex anions two citric acid resides are coordinated bidentatically to the BO4-terahedron. The values of the chemical bond lengths and bond angles in the complex anions are in accordance with those determined earlier for the crystal structures of dicitratoborates. The boron-containing five-membered rings are approximately planar. The cation (NH2CSHNH2) + is protonated at the sulphur atom. The protonation gives rise to delocalization of p-electron density at the C-S and N-C bonds. The bond lengths are: C-S 1.738(2) Å; N-C 1.317(3) Å and 1.298(3) Å. The bond C(sp 2 )-S is lengthened for 0.10 Å, but the C(sp 2 )-N bonds are shortened for 0.04 Å in average in the cation (HL) + when compared with the neutral molecule (L). In the crystals each organic cation is bonded with three nonidentical complex anions by five hydrogen bonds N-H … O (2+2) and S-H … O. The complex anions are bonded directly by four strong hydrogen bonds O-H … O (length from 2.589 to 2.692 Å).