Abstract “Isolation Characterization of Bioactive Isoflavone from Iris kashmiriana; and Synthesis, Modification and Biological Evaluation of Flavone Analogues” Iris Kashmiriana belongs to the family Iridaceae and a medicinal plant has been named Irsa in Iranian traditional medicines. This family comprises 3000 species and 85 genera. Amongst them, 12 species are found in India. This genus having diverse nature of the secondary metabolites, like isoflavones and their glycoside, flavones, benzoquinones, saponins and their glycoside stilbenes, sterols, triterpenoids and bufadienolides. The traditional and folk use of the plant of this genus gave the idea of diverse and prominent pharmacological activities like antibacterial, antiviral, antifungal, emetic, anticancer, antioxidant and anti-asthmatics. The wide spectrum of pharmacological activities associated with the isoflavones prompted us to undertake the phytochemical investigation of Iris kashmiriana, which is reported to be a rich source of isoflavones. Extraction followed by isolation of 12 new compounds has been done and name assigned as AJD-1 to AJD-12. AJD-4 and their analogues like AJD-6, AJD-8, AJD-10 were supposed to be new molecules. All the isolated compounds and their analogues were purified by melting point determination and Rf value analysis. The characterization and establishment of structure of all the isolated compounds and their analogues were done by chemically and spectroscopic method, like U.V. Spectrophotometer, IR,1H-NMR.13C-NMR , 2-D NMR and mass spectrometry. All the isolated compounds and their analogues were evaluated for their antioxidant, antibacterial, antifungal and cytotoxicity activity by MTT assay against MCF-7, MDAMB-231, A-549, PC-3 ,and Vero cell line followed by cell cycle analysis using Flow cytometer. Most of the compounds show moderate activity, whereas the compound AJD-4, AJD6. AJD-9 and AJD-12 have shown marked broad spectrum anticancer, antioxidant and antimicrobial activities. The compounds AJD-4, AJD-6 and AJD-5 have shown to induce cell cycle arrest at G2/ M phase The flavonoids and chalcones are polyphenolic compounds and universally present as constituents of flowering plants, particularly of food plants. Prop-2-en-1-one (chalcones) is a class of compounds that provides an option of developing inexpensive, synthetic therapeutic agents in the future. Prop-2-en-1-one and its derivatives have attracted particular interest during the last few decades due to use of such ring system as the core structure in many drug substances covering wide range of pharmacological application. An attempt has made to synthesized sixty compounds, out of which fifteen new dihydro methyl chalcones (Novelty of these compounds were well explained by Prentic Hall Frame Work Molecular Model) and fifteen dihydro pyrazole chalcones analogues were synthesized. All the synthesized compounds were purified by melting point determination and Rf value analysis. The characterization and establishment of the synthesized compounds were done by U.V, IR,1H-NMR.13C-NMR , and mass spectrometry. All the compounds were evaluated for their antioxidant (DPPH and ABTS methods), antibacterial, antifungal and cytotoxicity activity by MTT assay against MCF-7, MDAMB-231, A-549, PC-3, and Vero cell line.. Most of the compounds have shown moderate activity, whereas the compound KLD-4, 10, 15, and 7 have shown excellent antioxidant as well as anticancer activities. The compounds CASD-5, 7, 9 and 15 have shown marked anticancer and antioxidant activities. The compounds JAD-1, 9, 13, and 14 have shown excelent broad spectrum antimicrobial activities between 4.2 to 7.6 µg/ml (IC5O) against all microorganisms.