Azoles are characterized by high physiological activities. Five membered heterocycles incorporating two heteroatoms of which one must be nitrogen are called as azoles e.g. pyrazoles, imidazoles, benzimidazoles, thiazoles, thiadiazoles, oxazoles, oxadiazoles, triazoles, tetrazoles. These have been exploited in designing drugs and pesticides.Nitrogen containing azoles are well known for their versatile biological activities. Derivatives of pyrazoles, imidazoles, benzimidazoles, triazoles and tetrazoles possess fungicidal and herbicidal activities.Several heterocyclic compounds incorporating oxygen and nitrogen in the ring and possessing fungicidal144, bactericidal, herbicidal, antiviral and other activities are oxazoles, isooxazoles, benzoxazoles, oxadiazoles and oxazolidinones.The heterocyclic systems incorporating nitrogen and sulphur atoms display a wide range of biocidal activities and a large number of such compounds have been developed as useful pesticidal agents. Most important ring systems of these types are thiazoles, benzothiazoles, thiadiazoles and thiazolidinones.