Citrus essential oils were extraction from hydro distillation technique yielding Citrus oil with reasonable yield. Phytochemical screening of all five Citrus oils showed that alkaloids, tannins, sterols, terpenoids, saponoins, flavonoids were present (50-80%). GC/MS analysis showed highest percentage of limonene (58-89%) in Citrus oils. Antioxidant study revealed that Citrus peel oils have strong scavenging activity (83%-91%). Antimicrobial activity was evaluated by agar well method against eight common pathogens depicted marked antimicrobial potential especially tangerine (4.9-1.9 cm inhibition zones) and grapefruit oil (4.5-1.2 cm) inhibition zones. The studies emphasized the therapeutic and commercial utilization of Citrus peel essential oils as food preservatives, phytomedicine and antioxidant agent.

We describe the syntheses of half-sandwich complexes of the type [(η(5)-Cp(CONH-R))M(CO)3] with M = Re or (99m)Tc. The R group represents different tri-peptides (tpe) which display high binding affinities for oligopeptide transporters PEPT2. The (99m)Tc complexes were prepared directly from [(99m)Tc(OH2)3(CO)3](+) and Diels-Alder dimerized, cyclopentadienyl derivatized peptides in water. This approach corroborates the feasibility of metal-mediated retro Diels-Alder reactions for the preparation of not only small molecules but also peptides carrying a [(η(5)-Cp)(99m)Tc(CO)3] tag. We synthesized the Diels-Alder product [(HCpCONH-tpe)2] from Thiele's acid [(η(5)-HCpCOOH)2] via double peptide coupling. The Re-complexes [(η(5)-CpCONH-tpe)Re(CO)3] were obtained by attaching [(Cp-COOH)Re(CO)3] directly to the N-terminus of peptides as received from SPPS. The authenticity of the (99m)Tc-complexes is confirmed by chromatographic comparison with the corresponding rhenium complexes, fully characterized by spectroscopic techniques.

Antifungal activity of Monothecabuxifolia methanolic extract and its various fractions were assessed against Macrophominaphaseolina, a soil-borne fungal pathogen of more than 500 vegetal species as well as rare and emerging opportunistic human pathogen. Different concentrations of methanolic extract (3.125 to 200 mg mL−1) inhibited fungal biomass by 39–45%. Isolated n-hexane, chloroform and ethyl acetate fractions suppressed fungal biomass by 32–52%, 29–50% and 29–35%, respectively. Triterpenes lupeol and lupeol acetate (1, 2) were isolated from n-hexane while betulin, β-sitosterol, β-amyrin, oleanolic acid (3–6) were isolated from chloroform fraction. Vanillic acid, protocatechuic acid, kaempferol and quercetin (7–10) were isolated from the ethyl acetate fraction and identified using various spectroscopic techniques namely mass spectroscopy and NMR. Antifungal activity of different concentrations (0.0312 to 2 mg mL−1) of the isolated compounds was evaluated and compared with the activity of a broad spectrum fungicide mancozeb. Different concentrations of mencozeb reduced fungal biomass by 83–85%. Among the isolated compounds lupeol acetate (2) was found the highest antifungal against M.phaseolina followed by betulin (3), vanillic acid (7), protocatechuic acid (8), β-amyrin (5) and oleanolic acid (6) resulting in 79–81%, 77–79%, 74–79%, 67–72%, 68–71% and 68–71%, respectively. Rest of the compounds also showed considerable antifungal activity and reduced M.phaseolina biomass by 41–64%.

In vitro antifungal activity and phytochemical constituents of essential oil, aqueous, methanol and chloroform extract of Eucalyptus citriodora Hook leaves were investigated. A qualitative phytochemical analysis was performed for the detection of alkaloids, cardiac glycosides, flavonoids, saponins, sterols, tannins and phenols. Methanolic extract holds all identified biochemical constituents except for the tannin. While these biochemical constituents were found to be absent in essential oil, aqueous and chloroform extracts with the exception of sterols, cardiac glycosides and phenols in essential oil and sterols and phenols in aqueous and chloroform extracts. Antimycotic activity of four fractions of E. citriodora was investigated through agar-well diffusion method against four post-harvest fungi, namely, Aspergillus flavus Link ex Gray, Aspergillus fumigatus Fres., Aspergillus nidulans Eidam ex Win and Aspergillus terreus Thom. The results revealed maximum fungal growth inhibition by methanolic extract (14.5%) followed by essential oil (12.9%), chloroform extract (10.15%) and aqueous extract (10%).

In the title compound, C10H11N3O2S, the thia­zine ring exists in a conformation inter­mediate between twist-boat and half-chair. The dihedral angle between the mean plane of the thia­zine ring and the hydrazide group is 89.45 (13)°. In the crystal, N—H⋯O hydrogen bonds link the mol­ecules into (100) sheets and weak C—H⋯O inter­actions further consolidate the packing.

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IR studies have shown that the major constitutent of a labile gas-phase equilibrium in mixtures of trimethylalane and dimethylalane is the heteroleptic pentamethyldialane, Me,Al(pH)(pMe)AIMe, . A partial normal coordinate analysis of t h e spectra of isotopic variants reveals that this predominance arises from a significant strengthening of t h e AI-H-AI bridging bond. The experimental observations are supported by ab initio calculations of model systems. IR and variable temperature ' H NMR studies lead to similar conclusions for solutions of alane mixtures in toluene, and lend support for a ligand-exchange mechanism involving singly bridged species.Interest in the chemistry of simple alkyl derivatives of alane and gallane has recently undergone something of a renaissance, One factor influential in this revival is the widespread utilisation of these compounds as precursors to the deposition of A1 and Ga in semiconductor materials via processes such as metal organic chemical vapour deposition (MOCVD).' Thus both trimethylalane (TMA), Me,Al, and trimethylgallane, Me,Ga, have been used as Group 13 sources in the compound semiconductors GaAs and AlGaAs., However, these methyl compounds have not proved entirely satisfactory, largely because of substantial contamination by carbon, particularly in the case of Al., This fact has initiated a search for viable and economic alternative precursors. In the case of Ga, the problem has largely been solved by the use of triethylgallane, Et,Ga, where the lower activation /3-hydride elimination route effectively prevents production of the alkyl radicals widely held to be the principal culprits in carbon c ~n t a m i n a t i o n . ~~~ Unfortunately, the corresponding triethylalane is rendered a less practical source by its very low vapour pressure. This has led to searches in other directions, one of which has identified dimethylalane (DMA), Me,AlH, as a possible candidate for MOCVD pur-Paper 5/02063H ;

The condensation reactions of biacetyl with ortho-hydroxyaniline and 2-aminobenzoic acid to form bidendate NO donor Schiff bases were studied. The prepared Schiff base ligands were further utilized for the formation of metal chelates having the general formula [ML 2 (H 2 O) 2 ] where M = Co(II), Ni(II), Cu(II) and Zn(II) and L = HL 1 and HL 2 . These new compounds were characterized by conductance measurements, magnetic susceptibility measurements, elemental analysis, and IR, 1 H-NMR, 13 C-NMR and electronic spectroscopy. Both Schiff base ligands were found to have a mono-anionic bidentate nature and octahedral geometry was assigned to all metal complexes. All the complexes contained coordinated water which was lost at 141-160 °C. These compounds were also screened for their in vitro antibacterial activity against four bacterial species, namely: Escherichia coli, Staphylococcus aureus, Salmonella typhi and Bacillus subtilis. The metal complexes were found to have greater antibacterial activity than the uncomplexed Schiff base ligands.