فهرس المقالات Biscoumarins حرية الوصول المقاله صفحة الملخص نص كامل 1 - Melamine trisulfonic acid: An efficient and recyclable solid acid catalyst for the green synthesis of Biscoumarin derivatives Nasir Iravani Mosadegh Keshavarz Maryam Mousavi Mojtaba Baghernejad حرية الوصول المقاله صفحة الملخص نص كامل 2 - Silica-bonded n-propyldiethylenetriamine sulfamic acid as a recyclable solid acid catalyst for the synthesis of coumarin and biscoumarin derivatives Khodabakhsh Niknam Seyed Ahmad Sajadi Roghayeh Hosseini Mojtaba Baghernejad