Aparna Singh

New homo- and hetero-bimetallic assemblies based on 2,5-bis(4-carboxyphenylamino)-3,6-dichloro-1,4-benzoquinone: synthesis, characterization, and magnetic properties

Synthesis, characterization, and magnetic properties of a new series of dinuclear compounds MIIM′IIL2(H2O)4 (where MII, M′II = Mn (1), Ni (2), Cu (3) and MII = Cu, M′II = Co (4), Ni (5); LH2 = 2,5-bis(4-carboxyphenylamino)-3,6-dichloro-1,4-benzoquinone) are reported. These complexes were characterized by elemental analyses, FAB mass spectra, thermogravimetric analysis, spectroscopic techniques (infrared, NMR, UV-Vis), and powder XRD studies. Magnetic properties investigated by SQUID magnetometer show antiferromagnetic coupling between the metal centers connected by the extensive π-delocalized ligand. Magnetic coupling constants (J) ranging from −1.01 to −3.01 cm−1 based on the Hamiltonian H = −2JS i S j have been obtained. The optimized geometry of the ligand derived from DFT is also reported.

Synthesis, characterization and magnetic properties of cyanide bridged 1-D metal-coordination polymers based on [FeIII(s-bqdi)2(CN)2]−

A new series of transition metal complexes K[MII(s-bqdi)2][FeIII(s-bqdi)2(CN)2] · 10H2O (s-bqdi = semibenzoquinonediiminate, MII = Co (2), Ni (3), and Cu (4)) have been synthesized. These complexes have been characterized by elemental analyses, FT IR, Far IR, FAB mass, UV-Vis, TGA, CV measurements, and powder XRD. The powder XRD patterns of 2, 3, and 4 show that they are isostructural with hexagonal primitive lattice structures. The coordination polymers display 1-D chain networks. Magnetic properties of the CoIIFeIII complex studied by a SQUID magnetometer reveal low-temperature antiferromagnetic interaction.

Synthesis and characterization of binary and heterobimetallic complexes of dithiofuroate with 3d-metal ions

New complexes [M(dtf)2] (M=MnII or CuII), Cr(dtf)3 and V(dtf)4 (dtf=dithiofuroate) and heterobimetallic complexes M[Cd(dtf)4] (M=VO2+, MnII, FeII, CoII, NiII or ZnII) have been prepared in H2O−EtOH and characterized by elemental analyses, magnetic susceptibility measurements and spectroscopic studies. The known complexes Fe(dtf)3, Co(dtf)3, Ni(dtf)2, and Zn(dtf)2 have been screened towards the bacteria Pseudomonas spergillus and Bacillus spergillus. In vitro results of the binary complexes on P-815 (murine mastocytoma) indicate that these complexes show significant inhibition of [3H]thymidine and [3H]uridine incorporation in DNA and RNA in the tumour cells.

Development, Validation, and Verification of a Self-Assessment Tool to Estimate Agnibala (Digestive Strength)

According to Ayurveda, the traditional system of healthcare of Indian origin, Agni is the factor responsible for digestion and metabolism. Four functional states (Agnibala) of Agni have been recognized: regular, irregular, intense, and weak. The objective of the present study was to develop and validate a self-assessment tool to estimate Agnibala. The developed tool was evaluated for its reliability and validity by administering it to 300 healthy volunteers of either gender belonging to 18 to 40-year age group. Besides confirming the statistical validity and reliability, the practical utility of the newly developed tool was also evaluated by recording serum lipid parameters of all the volunteers. The results show that the lipid parameters vary significantly according to the status of Agni. The tool, therefore, may be used to screen normal population to look for possible susceptibility to certain health conditions.