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The reaction of CuCl2·2H2O with N-(p-nitrophenyl)-N′-butoxycarbonyl)-thiourea (H2nbt) and N-(o-nitrophenyl)-N′-(ethoxycarbonyl)-thiourea (H2net) gave two copper(I) complexes, [Cu(H2nbt)2Cl]2, 1, and Cu(H2net)2Cl, 2, respectively. In complex 1, the ligand H2nbt is S,S-bonded to two Cu atoms, and the two ligand molecules exchange “long” CuS interactions ( Cu  S = 2.700 A ) forming a dimer, in which the Cu atom has a distorted tetrahedral coordination ClCuS(1) = 119.9(1),ClCuS(2) = 122.9(1) and S(1)CuS(2) = 108.4(1)° and is 0.387(2) A from th basal S,S,Cl with unequal Cu  S [2.253(3), 2.244(3) A ] and Cu  Cl [2.247(3) A ] bonds. In complex 2, the copper (I) atom is inn a trigonal planar geometry [ClCuS(1) = 120.53(5), ClCuS(2) = 118.43(5) and S(1)CuS(2) = 119.16(5)°] with two unequal Cu  S [2.228(1), 2.232(1) A ] and Cu  Cl [2.251(1) A ] bonds.

Two polyhydroxylated steroids have been isolated from the South China Sea soft coral Sinularia microclavata, and their structures were established as 24-methylenecholestane-1 alpha,3 beta,5 alpha,6 beta-tetrol and 1 alpha,3 beta,5 alpha-trihydroxy-24-methylenecholestan-6-one from spectral evidence and from comparison with two reference compounds, numersterol A and 24-methylenecholestane-1 alpha,3 beta,5 alpha,6 beta, 25-pentol, which were isolated from the soft corals, Simularia numerosa and Sarcophyton glaucum, respectively.

A series of 2,4-disubstituted quinazoline derivatives found to be a new type of highly selective ligand to bind with telomeric G-quadruplex DNA, and their biological properties were reported for the first time.Their interactions with telomeric G-quadruplex DNA were evaluated by using fluorescence resonance energy transfer (FRET) melting assay, circular dichroism (CD) spectroscopy, surface plasmon resonance (SPR), nuclear magnetic resonance (NMR), and molecular modeling. Our results showed that these derivatives could well recognize G-quadruplex and have high selectivity toward G-quadruplex over duplex DNA. The structure-activity relationships (SARs) study revealed that the disubstitution of quinazoline and the length of the amide side chain were important for its interaction with the G-quadruplex. Furthermore, telomerase inhibition of the quinazoline derivatives and their cellular effects were studied. Refereed/Peer-reviewed