In recent years, composite materials have become well-known as catalyst, absorbent and sensor in modern science [1]. Quantum dots based on carbon, nitrogen and graphene as nano-materials with small size 10 nm have exhibited great potential uses in photocatalysis, biosensing, heavy metal elements sensing and biomolecule/drug delivery [2]. Despite the success of existing materials and technologies, the stability of CDs especially in harsh chemical and physical conditions and weak thermal stability is still highly desirable. Also, mesoporous silica catalysts are very much more functional due to their easy and fast separation from reaction media, which is high surface area, pore volume and tunable pore size. CQDs integrated with SBA-15 particles have been widely used as catalysts in chemical reactions due to their high porosity and increased chemical and thermal stability [3]. Compounds containing indole and barbituric acid have properties such as analgesic, antibacterial, anti-inflammatory, etc. Due to these properties, these compounds are widely used in various chemical reactions [4]. In this strategy, we have synthesized novel pyrazolo[4',3':5,6] pyrido[2,3-d]pyrimidine derivatives by one-pot condensation of benzaldehydes, pyrimidine-2,4,6(1H,3H,5H)-trione derivatives and as-synthesized 5-(1H-indol-3-yl)-1H-pyrazol-3-amine using CQDs-N(CH2PO3H2)2/SBA-15 as an excellent mesoporous heterogeneous catalyst (Scheme 1).
