Synthesis of novel heterocyclic organic compounds in ultrasonic media, their characterization and determination of their DPPH radical scavenging activity

Heterocyclic compounds and their derivatives have an important place in organic chemistry and they also have widely used in industrial and medical fields. The pharmacological properties of heterocyclic compounds are quite common. Heterocyclic compounds are cyclic compounds that include at least one heteroatom (S, O, N) in the ring. In our study, in order to contribute to the class of heterocyclic compounds, new spiro cyclic compounds have been synthesized under ultrasonic conditions or conventional heating methods according to green chemistry principles. The development of synthesis methods in accordance with the principles of green chemistry in organic chemistry has been of increasing importance in recent years and various studies have been carried out on this subject. Green chemistry is offered as an eco-friendly alternative to traditional chemistry applications for minimization or completely elimination of the usage and production of hazardous substances at chemical productions and processes. Spiro compounds have been preferred mostly because of their various biological activities and wide range of application areas. Spiro compounds are very important because of their pharmacological characteristics. It is known that they have biological activity properties such as anti-HIV, antifungal, antiviral, anticonvulsant, antitumor, antidepressant, antibiotic, analgesic, and anticancer. Furthermore, the catalysts used in the organic reactions are expected to have some properties such as being non-toxic, environmentally friendly, provide easy usage, being inexpensive, have high stability, and being reusable. In this study, new spirobenzoacridinedione and spiropyrazoloquinolindione derivative compounds were synthesized under different reaction conditions with isatin, aromatic amine and 1,3-dione compounds to contribute to the class of spiro ring compounds. In the reactions, camphor sulfonic acid (CSA) and triton x-100 were used as catalysts. Particular care has been taken to ensure that the catalysts used are particularly environmentally friendly. The novel compounds were synthesized by the single-pot method. In recent years, multi-component single-pot method has become one of the most important reaction methods of organic chemistry. The structures of all synthesized new compounds were determined by spectroscopic methods such as UV/VIS spectrophotometer, Fluorescence spectrophotometer, FTIR, 1H NMR, 13C (APT) NMR. In addition, DPPH radical scavenging activities as antioxidant activity of the synthesized compounds were investigated.