Uracil and its derivatives, such as pyrido [2,3-d] pyrimidines have received considerable attention over the past years because of their have biological activities such as, antibacterial, antiallergic, antimicrobial, tyrosine kinase, anti-inflammatory, analgesic, calcium channel antagonists, antihypertensive, tuberculostatic, antileishmanial, and antifungal [1-2]. A Mesoporous silica material (MSM), such as SBA-15, has surface area, good thermal stability, and potential for tunability due to its surface modifiable ability and nature of the MSM [3-6]. In this paper, there is growing interest in development of clean processes through involving green catalysts. Thus, in continuation of our pervious works on the application of reusable catalysts in organic synthesis, herein we decided to investigate the synthesis of pyrido [2,3-d] pyrimidines in the presence of SBA-15/(PO3H)2 as a recyclable green solid acidic catalyst
