Bis[4-(2-carbamoylhydrazin-1-yl­idene-κ2 N 1,O)-5-hydroxy­methyl-2-methyl­pyridinium-3-olato-κO 3]cobalt(II) dinitrate dihydrate

The asymmetric unit of the title compound, [Co(C9H12N4O3)2](NO3)2·2H2O, consists of a discrete cationic [Co(PLSC)2]2+ complex unit [PLSC is 4-(2-carbamoylhydrazin-1-yl­idene)-5-hydroxy­methyl-2-methyl­pyridinium-3-ol­ato], two NO3 − and two water mol­ecules. The two tridentate PLSC ligands of the cation are zwitterions related to each other by a non-crystallographic C 2 axis. The CoII ion is in a disorted octa­hedral coordination environment. The crystal structure is composed of alternating NO3/H2O and complex layers supported by extensive C—H⋯O, N—H⋯O and N—H⋯N hydrogen bonding

Selectivity of a thiosemicarbazonatocopper(II) complex towards duplex RNA. Relevant noncovalent interactions both in solid state and solution

Thiosemicarbazones and their metal derivatives have long been screened as antitumor agents, and their interactions with DNA have been analysed. Herein, we describe the synthesis and characterization of compounds containing [CuL]+ entities (HL = pyridine-2-carbaldehyde thiosemicarbazone) and adenine, cytosine or 9-methylguanine, and some of their corresponding nucleotides. For the first time, crystal structures of adenine- and 9-methylguanine-containing thiosemicarbazone complexes are reported. To the best of our knowledge, the first study on the affinity thiosemicarbazone–RNA is also provided here. Experimental and computational studies have shown that [CuL(OH2)]+ entities at low concentration intercalate into dsRNA poly(rA)·poly(rU) through strong hydrogen bonds involving uracil residues and π–π stacking interactions. In fact, noncovalent interactions are present both in the solid state and in solution. This behaviour diverges from that observed with DNA duplexes and creates an optimistic outlook in achieving selective binding to RNA for subsequent possible medical applications.Obra Social “la Caixa” (OSLC-2012-007), Ministerio de Economía y Competitividad and FEDER funds (CTQ2013-48937-C2-1-P, CTQ2015-70371- REDT, MAT2012-34740 and CTQ2014-58812-C2-2-R), Junta de Castilla y León (BU237U13), the Basque Government (IT-779- 13), Gerencia Regional de Salud, Consejería de Sanidad, Junta de Castilla y León (GRS 1023/A/14 and GR172)