From the preceding discussion following conclusions can be drawn, * These hydrazone ligands can easily make stable metal coordination complexes with different heavy metals (Cu, Ni and Zn) .They are bidentate and form complexes in enolic
mode as derived from IR spectra and x-rays crystallographic data.
FTIR: 1608 (C=C), 1620 (C=N);, 1678 (C=O amidic), 3366 (-OH enolic
); [sup.1]H NMR (600 MHz, DMSO-[d.sub.6]) [[delta].sub.H]: 2.07 (3H, s, -CO[[CH.bar].sub.3]); 2.37, 2.41 (6H, 2S, 2 C[H.sub.3]); 3.71, 3.90 (2H, 2d, -C[H.sub.2]- of thiazolidine ring J = 16.2 Hz), 5.90 (2H, s, -C[H.sub.2]), 6.07 (1H, s, [C.sub.3]-H), 7.24 (1H, d, [C.sub.6]-H, J = 7.8 Hz), 7.66, 7.75 (4H, 2d, for p-disubstituted benzene J = 8.4 Hz), 8.29 (1H, s, [C.sub.2]-H of thiazolidinone), 8.39 (1H, d, [C.sub.5]-H, J = 7.8 Hz).
(b) PPAG, enolic
) (MeOH) max] L[H.sub.3](I) -- -- -- 9260, [[Co(LH)(MeOH)].sub.2] 1255 975 13220, 19280 [[Cu(LH)].sub.2] -- -- 18100 [Zn(LH)[(MeOH).sub.2]] -- 960 -- [Zr[(OH).sub.2](LH)(MeOH)] -- 985 -- [Mo[O.sub.2](LH)[(MeOH).sub.2]] 1240 965 -- Compound Mag.
[HL.sup.1] reacted as the enol-imino form (Figure 1 (5)), when coordinated to metal ions in solution, coordinating via pyrazolone ring enolic
(C-O), azomethine (C=N), and hydrazide side chain (C=O).
GRE contained higher levels of all compounds, except the enolic
phenylpyruvic acid-2-O-glucoside and luteolin-7-O-glucoside.
As is evident from the above data, the Schiff base ligands(1a-3a) behave as dibasic tridentate ligands and co-ordinate through phenolic oxygen, azomethine nitrogen and enolic
(4) Meloxicam is a member of the enolic
class of NSAIDs that, at low doses, have been reported to inhibit preferentially the cycloxygenase-2 (COX-2) prostaglandin metabolic pathway.
Aspalathin, nothofagin and PPAG (enolic
phenylpyruvic acid-2-0-glucoside) were quantified at 288 nm, while orientin, isoorientin, vitexin, isovitexin, hyper-oside, isoquercitrin, rutin, quercetin-3-0-robinobioside (as rutin equivalents), luteolin-7-0-glucoside and ferulic acid were quantified at 350 nm using 5-point calibration mixtures.
Meloxicam is a NSAID in the group of the enolic
acids found to preferentially inhibit cyclooxygenase-2 (COX-2) rather than cyclo-oxygenase-1 (COX-1), the latter being responsible for physiologic processes such as renal and gastric mucosal protection.