Gurvinder S. Sodhi

Powder method for detecting latent fingerprints: a review

The powder technique for detecting latent fingerprints involves the application of a finely divided formulation to the fingermark impression, generally with a glass-fibre or a camel hair brush. The powder gets mechanically adhered to the sweat residue defining the ridge pattern. The furrows which are devoid of the fingerprint residue, do not adhere the powder onto them. The final outcome is that the powder formulation sticks to the ridges, but is easily blown off the furrows. Since the powder is normally coloured, the ridge pattern becomes visible and the latent print is said to have developed.

Phosphide poisoning: A review of literature

Metal phosphides in general and aluminium phosphide in particular are potent insecticides and rodenticides. These are commercially used for protection of crops during storage, as well as during transportation. However, these are highly toxic substances. Their detrimental effects may range from nausea and headache to renal failure and death. It is, therefore, pertinent to ensure their circumspect handling to avoid poisoning episodes. Its poisoning has a high mortality and recent years have seen an increase in the number of poisoning cases and deaths caused by suicidal ingestion. Yet due to their broad spectrum applications, these chemicals cannot be written off. The present communication reviews the various aspects of toxicity associated with metal phosphides.

ORGANOMERCURY(II) COMPLEXES OF KOJIC ACID AND MALTOL : SYNTHESIS, CHARACTERIZATION, AND BIOLOGICAL STUDIES

A number of organomercury(II) complexes of kojic acid (HL1, I) and maltol (HL2, II) of the type p-XC6H4HgL1 (III) and p-XC6H4HgL2 (IV) [X = Me, MeO, NO2] have been synthesized and characterized. [formula: see text] Conductance measurements indicate the nonelectrolyte behavior of the complexes. From IR and UV studies, the bonding modes of the ligands to the organomercury(II) moieties have been elucidated. The 1H and 13C NMR spectra support the stoichiometry of the complexes. The fragmentation pattern has been analyzed on the basis of mass spectra. From thermal studies (TG and DTA), various kinetic and thermodynamic parameters for thermal degradation have been enumerated. The complexes have been screened against some pathogenic bacterial strains. The bactericidal activity has been correlated with the thermal data.

Semi-synthetic antibiotics: Titanium(IV), zirconium(IV) and mercury(II) complexes of 6-amino penicillinic acid

Abstract A number of organometallic derivatives involving 6-amino penicillinic acid ( I ), of the types η 5 -R) 2 M- (Cl)L − Et 3 NH + ( II ), (η 5 -R) 2 M(Cl)L ( III ) and R′HgL [R = cyclopentadienyl (C 5 H 5 ), indenyl (C 9 H 7 ), R′ = phenyl (C 6 H 5 ), p -acetoxyphenyl ( p -CH 3 COOC 6 H 4 ), o -hydroxyphenyl ( o -HOC 6 H 4 ), p -hydroxyphenyl ( p -HOC 6 H 4 ); M = Ti(IV), Zr(IV); LH = 6-amino penicillinic acid] have been synthesized and characterized. Conductance measurements indicate that while the (η 5 -R) 2 M(Cl)L − Et 3 NH + complexes are 1:1 electrolytes, the remaining compounds are non-electrolytes. From IR and UV spectral studies it is concluded that the penicillin moiety is bidentate. PMR and CMR studies support the stoichiometry of the complexes. Fluorescence studies have been carried out for o - and p -HOC 6 H 4 HgL complexes and relevant photochemical parameters have been elucidated. X-ray diffraction studies have been made for the o -HOC 6 H 4 HgL complex. For the C 6 H 5 HgL, p -CH 3 COOC 6 H 4 HgL and p -HOC 6 H 4 HgL complexes, thermal studies (TG and DTA) have been carried out and kinetic parameters for thermal degradation have been enumerated. In addition, the fragmentation pattern of these complexes has been analysed on the basis of mass spectra. The C 6 H 5 HgL and p -CH 3 COOC 6 H 4 HgL complexes show positive bactericidal activities.

Structure Determination and Anti-Inflammatory Activity of some Purine Complexes.

Organomercury(II)-purine derivatives of the type, p-MeOC6H4HgL1 (I), p-NO2C6H4HgCl(L2)(II), p-MeC6H4HgCl(L3)(III) and p-NO2C6H4HgCl(L3)(IV) [ HL1 = theophylline, L2 = theobromine, L3 = caffeine] have been synthesised and characterised on the basis of spectral studies (IR, UV, 1H & 13C NMR). The complexes have been screened for anti-inflammatory activity.

Thermal studies on platinum metal complexes of N-methylcyclohexyl dithiocarbamate

Abstract Platinum metal complexes of N -methylcyclohexyl dithiocarbamate of the type [MecyhxNCS 2 ] n M [cyhx = cyclohexyl; M = Pd, Pt ( n = 2); Ru, Rh, Ir ( n = 3); Os ( n = 4)] have been synthesised. Spectral studies (IR and UV) indicate that the dithiocarbamate moiety is bidentate. From thermogravimetric (TG) curves, the order and activation energy of the thermal decomposition reaction have been elucidated. The variation of activation energy has been explained on the basis of hard and soft acid base (HSAB) theory. From differential thermal analysis (DTA) curves, the heat of reaction has been calculated.

Dihiocarbamate Anions as Salts of Oxinate Chelates of Titanium(IV)

Abstract (η5-Cyclopentadienyl) (η5-pyrrolyl)titanium(IV) dichloride, (η5-Sndenyl)(η5-pyrrolyl)titanium(IV)dichloride and (η5-cyclopentadienyl)(η5-indenyl)titanium(IV)dichloride, when treated with oxine in aqueous medium form ionic derivatives of the type [(η5-R)(η5-R′)TiL]+Cl− (R = C6H5, C9H7, R′ = C4H4N; R = C5H5, R′ = C9H9; L is the conjugate base of oxine). These react with dithiocarbamate anions in aqueous solution giving ionic complexes of the type (η5-R)(η5-R′)TiL]+X (X = Ne2NCS2 −, Et2NCS2 − and i-Pr2NCS2 −). IR and 1H NMR studies demonstrate that the ligand L is chelating in all the cases. Consequently, there is tetrahedral coordination about the titanium atom.

Preparation and Characterisation of Bis(η5-indenyl)-N,N′-disubstituted Dithiocarbamatochloro Oxomolybdenum(VI) Complexes

Abstract Bis(η5-indenyl)N,N′-disubstituted dithiocarbanatochloro oxomolybdenum(VI) complexes of the type (C9H7)2MoO(S2CNR2)Cl and (C9H7)2MoO(S2CNRR′)Cl (where R = Me, Et, i-Pr and R′ = cyhx) have been prepared by the reaction of stoichiometric amounts of bis(η5-indenyl) oxomolybdenum(VI) dichloride with sodium salts of dithiocarbamic acids in refluxing dichloromethane. Infrared spectral studies demonstrate that in these complexes, dithiocarbamate ligands are bidentate. Therefore the molybdenum (VI) atom may be assigned the coordination number 7 in all these complexes. In addition to infrared studies, electronic spectra, NMR studies, magnetic susceptibility, elemental analyses and conductance measurements have been carried out for these complexes.

Studies on organomercury(II) complexes of isoniazid

A number of organomercury(II) complexes involving isoniazid (I), of the type RHgCl(L)(II) [R = phenyl(C6H5), o-hydroxyphenyl (o-HOC6H4), p-hydroxyphenyl (p-HOC6H4), p-acetoxyphenyl (p-AcOC6H4), 2-furyl (2-C4H3O); L = isoniazid] have been synthesized and characterized. Conductance measurements indicate that the complexes are nonelectrolytes. From IR and UV studies, it is concluded that isoniazid acts as a bidentate ligand, coordinating through hydrazinic nitrogen and carbonyl oxygen. 1H and 13C NMR support the stoichiometry of the complexes. From fluoroscence studies a number of photochemical parameters have been elucidated. For the C6H5HgCl(L), p-HOC6H4HgCl(L), and p-AcOC6H4HgCl(L) complexes, thermogravimetric studies have been carried out and relevant kinetic and thermodynamic parameters for thermal degradation have been enumerated. In addition, the fragmentation pattern of the complexes has been analyzed on the basis of mass spectra. The C6H5HgCl(L) and p-HOC6H4HgCl(L) complexes have been screened for tuberculosis activity.

Fingermarks detection by eosin-blue dye.

Eosin-blue (I) dye, along with a phase transfer catalyst, has been used to detect latent fingerprints on a wide range of surfaces, including paper, glass, steel, lamination sheets, polythene, plastic and bakelite.