2-Substituted (S)-2-(3,3-dimethyl-1-oxo-10,10a-dihydroimidazo[1,5-b]isoquinolin-2(1H,3H,5H)-yl)acetic acids: Conformational prediction, synthesis, anti-thrombotic and vasodilative evaluation

Diversity-oriented synthesis of medicinally important 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) derivatives and higher analogs

1,2,3,4-Tetrahydroisoquinoline-3-carboxylic acid (Tic) is a constrained analog of phenylalanine (Phe). The Tic unit has been identified as a core structural element present in several peptide-based drugs and forms an integral part of various biologically active compounds. This report covers the biological significance of the Tic core and provides a detailed account of various synthetic approaches available for the construction of Tic derivatives. Along with the traditional methods such as the Pictet-Spengler and Bischler-Nepieralski reactions, we cover various recent approaches such as enyne metathesis, [2 + 2 + 2] cycloaddition and the Diels-Alder reaction to generate Tic derivatives. In addition, syntheses of higher analogs of Tic are also discussed.