An expedient, regioselective synthesis of novel 2-alkylamino- and 2-alkylthiothiazolo[5,4-e]- and -[4,5-g]indazoles and their anticancer potential

Several novel 2-alkylamino- and 2-alkylthiothiazolo[5,4-e]- and -[4,5-g]indazoles and their 6-alkyl and 8-alkyl derivatives have been synthesised in high overall yields starting from 5-nitro and 6-nitroindazoles in a three-step route involving the regioselective cyclisation of thioureidoindazoles and indazolyl dithiocarbamates as the key steps. Some assorted thiazoloindazoles have been screened for anticancer properties, which demonstrated the anticancer potential of at least one product, justifying its further follow-up.     

COPPER(III) DITHIOCARBAMATE COMPLEXES FROM THIURAM DISULFIDES AND COPPER(I) HALIDES

Abstract

Tetraalkylthiuram disulfides react with Cu(I) halides to give materials of composition Cu₂(dtc)₃X₂, which are presumed to be the ionic species Cu (dtc)₂ ⁺Cu (dtc)X₂ ⁺ containing Cu(II) and Cu(III), on the basis of magnetic susceptibilities, IR and ESCA spectroscopies. In the presence of triphenylphosphine, sulfur abstraction from the monosulfides leads to known monosulfide complexes of Cu(I). Some of the dithiocarbamate complexes are also accessible through degradation of alkylimonium trithiolane and tetrathiolane halocuprate(I) compounds.     

Tertiary phosphine-appended transition metal ferrocenyl dithiocarbamates: Syntheses,Hirshfeld surface,and electrochemical analyses

Five new heteroleptic complexes of Cu(I), Ag(I), and Ni(II) having formulae [Cu₃(dtc)₂(dppf)₂]PF₆ ( Cu-I ), [Cu₃(dtc)₂(dppe)₂]PF₆ ( Cu-II ), [Cu(PPh₃)₂(dtc)] ( Cu-III ), [Ag₃(dtc)₂(PPh₃)₂]NO₃ ( Ag-I ), and [Ni(dtc)(dppf)]PF₆ ( Ni-I ) (dtc = N-ethanol-N-methylferrocenyl-dithiocarbamate; dppf = 1,1′-bis(diphenylphosphino)ferrocene; dppe = 1,1′-bis(diphenylphosphino)ethane; PPh₃ = tripheylphosphine) have been synthesized and characterized using elemental analysis, Fourier-transform infrared, multinuclear nuclear magnetic resonance, UV–Vis spectroscopy, and single-crystal X-ray diffraction. The single-crystal X-ray diffraction studies indicate that Ag-I forms a rare trinuclear cluster in which the geometry around the two silver centers Ag1 and Ag3 is distorted tetrahedral, whereas the third silver center Ag2 shows a distorted trigonal planar geometry. The Ni-I complex has a distorted square-planar geometry around the Ni center. In addition, a side product [Ag₂{S₂(dppf)₂}] ( Ag-II ) was obtained during an attempt to synthesize [Ag(dppf)(dtc)], where the two Ag centers are bridged by two sulfido centers and coordinated with two phosphorus centers of the dppf ligand to give rise to a distorted tetrahedral geometry. The solid-state structures of Ag-I , Ni-I , and Ag-II are stabilized by a variety of weak interactions. The nature of these interactions has been addressed with the help of Hirshfeld surface analyses. In addition, the weak argentophilic interaction in Ag-I and Ag-II have been studied using quantum theory of atoms in molecules and natural bond orbital calculations. The electrochemical properties of the complexes have been investigated using cyclic voltammetry, where Cu-I and Cu-II exhibited two quasi-reversible waves, whereas Cu-III , Ag-I , Ag-II , and Ni-I exhibited only one quasi-reversible peak.     

Synthesis of nickel sulfide and nickel–iron sulfide nanoparticles from nickel dithiocarbamate complexes and their photocatalytic activities

[ Ni(dtc)₂] (dtc = N-(pyrrole-2-ylmethyl)-N-thiophenemethyldithiocarbamate ( 1 ), N-methylferrocenyl-N-(2-phenylethyl)dithiocarbamate ( 2 ), N-furfuryl-N-methylferrocenyldithiocarbamate ( 3 ), and (N-[pyrrole-2-ylmethyl]-N-thiophenemethyldithiocarbamato-S,S′)(thiocyanato-N)(triphenylphosphine)nickel(II) ( 4 ) complexes were prepared and characterized by elemental analysis, infrared, ultraviolet–visible, and nuclear magnetic resonance (¹H and ¹³C) spectroscopies. The data were consistent with the formation of square planar nickel(II) complexes, which was confirmed by single-crystal X-ray diffraction studies on 2 and 4 . Fe···Fe interactions exhibited by complex 2 led to supramolecular aggregation. The structure of 4 reveals intermolecular and intramolecular C-H···Ni anagostic interactions. The anion-sensing properties of 2 were studied with halide ions by cyclic voltammetry. It was observed that 2 acts as sensor for bromide. Complexes 1 , 2 , and 3 , were utilized to prepare nickel sulfide, nickel–iron sulfide-1, and nickel–iron sulfide-2, respectively. The composition, structure, morphology, and optical properties of nickel sulfide and nickel–iron sulfides were examined using powder X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, ultraviolet–visible, fluorescence, and infrared spectroscopy. Powder X-ray diffraction patterns of nickel sulfide, nickel–iron sulfide-1, and nickel–iron sulfide-2 indicate the formation of orthorhombic Ni₉S₈, cubic NiFeS₂, and cubic Ni₂FeS₄, respectively. The photocatalytic activities of as-prepared nickel sulfide and nickel–iron sulfide-1 nanoparticles were investigated for photodegradation of methylene blue and rhodamine-B under ultraviolet irradiation. Nickel–iron sulfide-1 nanoparticles show slightly higher photodegradation efficiency compared with the nickel sulfide nanoparticles.     

Spectrophotometric study of complex formation equilibria of Ni(II) ion with benzyl-, phenyl- and dibutyldithiocarbamates

Complex formation equilibria between Ni(II) with benzyldithiocarbamate, phenyldithiocarbamate and dibutyldithiocarbamate have been studied spectrophotometrically at (25±0.1)°C in 0.1M diethanolamine/diethanolamonium ionic strength and pH 8.8 that prevents ligand decomposition, frequent in acid medium. The stability constants and molar absorptivity coefficients have been evaluated for the three complex species obtained in each case.     

Preparation of copper-indium sulfide thin films by single-source OMCVD: Mass-spectral investigation of decomposition path of the organometallic sources

In order to prepare high-quality CuInS₂ thin films vapor phase decomposition patterns of three copper-indium binuclear complexes, and as candidates for source materials were investigated using EI MS. The complex 1c showed series of intensive peaks due to the fragmentation of M⁺. For 1a, only a fragmentation pattern starting from BuIn(S₂CNBu₂)₂ was detectable. This should suggest that 1a decomposed into BuIn(S₂CNBu₂)₂ and copper sulfide before vaporization. In addition an ambiguous feature could be observed for 1b, viz. two fragmentation paths. Consequently, we judge that 1c is a suitable source complex to prepare CuInS₂ thin films via a single-source OMCVD process. Thus chalcopyrite CuIns₂ thin films were successfully prepared via single-source OMCVD using 1c as a source complex, with T_substrate400°C, T_source80°C, base pressure 0.7 Torr and carrier (nitrogen) flow rate 0.8 L min^?1. Fragmentation of two copper dithiocarbmates, Cu(S₂CNBu₂)₂ and Cu[S₂CN(i-Pr)₂]₂, and two butylindium thiolates, Bu₂InS(i-Pr) and BuIn[S(i-Pr)]₂, as components of 1 is additionally discussed.     

Über Chalkogenolate. 204. Reaktion von Acetamid mit Kohlenstoffdisulfid. 1. Darstellung und Eigenschaften von N-Acetyldithiocarbamaten

On Chalcogenolates. 204. Reaction of Acetamide with Carbon Disulfide. 1. Synthesis and Properties of N-Acetyl Dithiocarbamates Acetamide reacts with carbon disulfide in the presence of a strong base to form via the tetrabutyl ammonium salt the N-acetyl dithiocarbamates M[S₂C? NH? CO? CH₃] with M = Na, K, Rb, Cs, [N(ⁿC₄H₉)₄]. The new compounds have been characterized by means of electron absorption, infrared, nuclear magnetic resonance (¹H and ¹³C), and mass spectra. Attempts to synthesize N-acetyl dithiocarbamic acid were not successful.     

Synthesis and characterization of copper(II) dithiocarbamate complexes involving pyrrole and ferrocenyl moieties and their utility for sensing anions and preparation of copper sulfide and copper–iron sulfide nanoparticles

Bis(N‐(pyrrol‐2‐ylmethyl)‐N‐butyldithiocarbamato‐S,S′)copper(II) ( 1 ), bis(N‐(pyrrol‐2‐ylmethyl)‐N‐(2‐phenylethyl)dithiocarbamato‐S,S′)copper(II) ( 2 ), bis(N‐methylferrocenyl‐N‐(2‐phenylethyl)dithiocarbamato‐S,S′)copper(II) ( 3 ) and bis(N‐furfuryl‐N‐methylferrocenyldithiocarbamato‐S,S′)copper(II) ( 4 ) were prepared and characterized using elemental analysis and infrared and UV–visible spectroscopies. X‐ray diffraction (XRD) studies on 3 show that each copper centre adopts the square planar geometry by the coordination of four sulfur atoms of the metalloligand N‐methylferrocenyl‐N‐(2‐phenylethyl)dithiocarbamate. The Cu? S distances are symmetrical and are in the range 2.293–2.305 Å. The supramolecular architecture in complex 3 is sustained in the solid state by C? H???π, C? H???S, Fe???Fe and H???H interactions. Density functional theory calculations were carried out for 3 . Anion (F^?, Cl^?, Br^? and I^?) binding studies with complex 1 were performed using cyclic voltammetry. Copper sulfide, copper–iron sulfide‐ 1 and copper–iron sulfide‐ 2 nanoparticles were prepared from complexes 2 , 3 and 4 , respectively, and they were characterized using powder XRD, transmission electron microscopy (TEM) and energy‐dispersive X‐ray, UV–visible, photoluminescence and infrared spectroscopies. TEM images of copper–iron sulfide‐ 1 and copper–iron sulfide‐ 2 reveal that the particles are spherical and oval shaped, respectively. Photocatalytic activities of as‐prepared nanoparticles were studied by decolourization of methylene blue and rhodamine‐B under UV light. It was found that copper–iron sulfide degrades methylene blue and rhodamine‐B much better than does copper sulfide.     

Preparation of Mixed Carbamic/Dithiocarbamic Anhydrides via Silyl Carbamates or Silyl Dithiocarbamates

The reactions of silyl carbamates and silyl dithiocarbamates with different acid chlorides (carbamoyl/thiocarbamoyl chloride, chloroformates, etc.) have been studied. The obtained mixed anhydrides have different thermal stability.     

Synthesis,spectra, crystal structures and anticancer studies of 26‐membered macrocyclic dibutyltin(IV) dithiocarbamate complexes: Single‐source precursors for tin sulfide nanoparticles

Four new macrocyclic dinuclear dibutyltin(IV) dithiocarbamate complexes of the type [Bu₂Sn(dtc)]₂, where dtc = hexane‐1,6‐diylbis(4‐fluorobenzyldithiocarbamate) anion ( 1 ), hexane‐1,6‐diylbis(4‐chlorobenzyldithiocarbamate) anion ( 2 ), hexane‐1,6‐diylbis(furfuryldithiocarbamate) anion ( 3 ) and hexane‐1,6‐diylbis(pyrrole‐2‐ylmethyldithiocarbamate) anion ( 4 ), have been prepared. The dithiocarbamate ligands efficiently self‐assemble with Bu₂Sn(IV) to form bimetallic 26‐membered macrocycles. All the complexes have been characterized using elemental analysis, infrared and NMR (¹H and ¹³C) spectroscopies and X‐ray crystallography. Single‐crystal X‐ray diffraction analysis of all the complexes confirms the formation of the dinuclear metallomacrocycles in which dithiocarbamate ligands are asymmetrically bound to the tin atoms. The coordination sphere around the tin atom in 1 – 4 can be described as a skew trapezoidal bipyramid. The dimensions of the cavity of the macrocycles of 1 – 4 are ca 8.0 × 9.0 Å². Complexes 1 – 4 were evaluated for their in vitro anticancer activity against MCF‐7 and HL‐60 cells. Complexes 1 and 2 are more active against MCF‐7 and HL‐60. Thermal decomposition of 1 and 4 yielded tin sulfides. They were characterized using powder X‐ray diffraction (PXRD), high‐resolution transmission electron microscopy and UV diffuse reflectance and energy‐dispersive X‐ray spectroscopies. PXRD studies reveal that the as‐prepared tin sulfides are composed of orthorhombic phase of SnS.