The synthesis of 2-[(1,3-diphenyl-1H-1,2,4-triazol-5-yl) dinitromethyl]-5,6,8,8a-tetrahydro-[1,2,4] oxadiazol[3,2-c][1,4] oxazine is caused by the reaction of morpholine interaction in the presence of hydrogen peroxide with 2-(1,3-diphenyl-1H-1,2,4-triazol-5-yl)-2,2-dinitroacetonitrile and sodium tungstate in a catalytic amount. The latter interacts with an excess of KOH in ethanol to form the potassium salt aci-5-dinitromethyl-1,3-diphenyl-1H-1,2,4-triazole and 5,6,8,8a-tetrahydro-[1,2,4] oxadiazole[3,2-c] [1,4] oxazine-2-ol. The ability of compounds 3-5 to inhibit the growth and development of museum strains of Staphylococcus aureus RP, E. coli O39, Pseudomonas aeruginosa 143 and clinical strain of Streptococcus pneumonia, as well as clinically significant species of fungi Trichophyton rubrum, Microsporumcanis and Candida albicans was investigated. It was revealed that the compounds have bacteriostatic activity against the studied bacterial strains: 3 and 4 expressed in a range of low concentrations. Compounds 3-5 demonstrate a fungistatic effect: compound 3 in a range of low concentrations. In relation to fungal strains, compounds 3-5 demonstrate a fungistatic effect: compound 3 in the range of low concentrations. Thus, as a result of the implementation of the "one pot" process, it is possible to embed oxadiazoline and oxazine cycles into the main (central) part of the compound 1 molecule, which leads to the synthesis of new drugs with antimicrobial and antifungal activity.