Isolation of secondary metabolites from Syzygium aromaticum (L.) Merr. & L.M.Perry. (cloves), and evaluation of their biological activities.

Phytochemical investigation of dried flower buds of (L.) Merr. & L.M.Perry. (clove) led to the isolation and identification of fourteen known compounds, oleanolic acid (), betulinic acid (), methyl benzoic acid (), sabrinic acid () eucalyptolic acid (), nigricin (), 3----coumaroylmaslinic acid (), methyl maslinate (), maslinic acid (), 3, 4, 5-trimethoxy-3',4'-,-methylideneflavellagic acid (), lantanone () 3,4,3'-trimethoxyellagic acid (), 11-oxo-oleanolic acid (), and -sitosterol-3---D-glucopyranoside (). Their structures were identified by H NMR, C NMR, Mass spectroscopic techniques, and comparison with the literature data. Compounds , and showed a strong mortality against root knot nematode, at 0.125% concentration after 72 hours (88-92% inhibition). Compound showed a good anti-glycation activity with IC = 142.0 ± 1.8 M when compared with standard, i.e. rutin (IC = 54.59 ± 2.20 M). Compound showed a comparable urease inhibitory activity (IC = 26.1 ± 0.19 M) with the positive control thiourea (IC = 24.5 ± 0.34 M).