Synthetic approach towards anti-inflammatory agent, daibucarboline a and its derivatives via tetrahydro- β-carboline intermediates / Nur Ain Nabilah Ash’ari

β-Carbolines, belonging to the class of indole alkaloids, were isolated from wild Syrian rue (Peganum harmala), which is common in Iran. Over the past few decades, the synthesis of β-carbolines has elicited much interest due to its wide pharmaceutical and biological applications. For instance, one of their many derivatives, the daibucarboline A 1, is proved to demonstrate interesting anti-inflammatory activity upon tested using iNOS assay with the IC50 value of 18.41 μM. However, literature survey reveals there is no report found on the synthesis of daibucarboline A 1 in addition to limited works on its isolated compound. Thus, we described herein the synthetic approach towards daibucarboline A 1 and its derivatives by using different substituted indoles and aldehydes/glyoxal. The first part is the chemical studies towards the intermediates and derivatives of daibucarboline A 1 using tryptamine 29 as the starting material with different substituted benzaldehydes 30-42 to afford a series of key 1-substituted tetrahydro-β-carboline intermediates 43-55 in 20-95 % yields.