The present disclosure generally relates to substituted heteroaromatic compounds. The invention relates to novel substituted 4-
heteroatom-isoquinolone compounds, and isomers, derivatives, analogues and / or salt forms thereof of formula I; and its process of preparation thereof. Furtherore, the present invention relates to a process of preparation of various drugs / APIs / alkaloids e.g. Ampikin APIs such as CX-614, CX-554, DRF-2655, ITF-296, ITF-1129, Raititrexed, Deoxyvasicinone family of
quinazolinone alkaloids, etc. using said formula I compound as starting material. The compound of formula I acts as
antimalarial agent, anticancer agent, neuroprotective agent and so on. Formula I