ChemInform Abstract: Tamarind Fruit Juice as a Natural Catalyst: An Excellent Catalyst for Efficient and Green Synthesis of Bis-, Tris-, and Tetraindolyl Compounds in Water

ingredients 11 of 100 g of pulp of tamarind fruit contain water (15-30%), protein (2-9%), fat (0.5-3%), total carbohydrate (56-82%), edible fiber (2.2-18.3%), ash (2.1-3.3%), calcium (81-466 mg), phosphorous (86-190mg), iron (1.3-10.9 mg), sodium (23-28 mg), potassium (62-570 mg). It also contains 41-58% sugars of which 25-45% is in the form of reducing sugars and 16% is in the form of non-reducing sugars and tartaric acid (8-18%) and ascorbic acid (3-9 mg). The composition of the tamarind fruit juice varies with geographical, cultural and seasonal harvesting and processing. An aqueous extract of tamarind fruit juice is acidic having pH 3.0 and acidity percentage is 50.3% and hence it will be work as an acid catalyst for condensation of carbonyl compounds and indoles. Therefore, we have used this fruit extract as natural catalyst for synthesis of bis-, tris-, and tetraindolyl compounds.