A noval derivatives of 3-substituted[1,2,4]triazolo[4,3-b]pyridazine (4a−4o) and 7,8,9,10-tetrahydrobenzo[4,5] thieno[2,3-d][1,2,4]triazolo[4,3-b]pyridazine (7a−7l) is prepared by the reaction of heteroaryl hydrazone from the aldehyde and pyridazinohydrazine derivative, followed by subjecting the intermediate directly to oxidative cyclization employing the mixture of Me4NBr and Oxone. These derivatives were subjected to preliminary antimicrobial activities against microorganism. All these compounds exhibit good to moderate activity.

Endophytic fungi are the main sources of novel bioactive compounds because of their unique inhabitation ability. This work focus on studying the diversity of fungal endophytes from eleven aromatic plants in three locations of Bhadra Wildlife Sanctuary i.e. Baba Budangiri, Lakkavalli, Mullayanagiri and screened for antimicrobial potential. Three hundred and forty-three endophytic fungi were isolated, and the highest colonization frequency was in Plectranthus amboinicus (60%) collected from the Baba Budangiri region. Fusarium sp., was the most prominent genus isolated from all plant samples. The relative density (RD) of isolates varied within plant parts, with leaf fragments of the Baba Budangiri region having the highest RD 42% and root segments showed the least RD value from all three locations. The Shannon-Wiener and species richness was highest in the Lakkavalli region. The Jaccard's similarity indices of fungal endophytes compared between the three sites ranged from 0.33-0.38. The antimicrobial activity showed that the endophyte Chaetomium globosum had maximum inhibition of 22 mm against Escherichia coli and Bacillus subtilis. Also, a wide range of antifungal activity was exhibited by C. globosum, inhibiting the radial growth of Fusarium oxysporum by 74.5%. C. globosum can be further exploited for the production of bioactive compounds.