<p><i>Aegle marmelos</i> is a plant species native to India. Commercially available food products such as jam, jelly, candy, squash etc. are prepared from ripe fruit pulp of <i>A. marmelos</i>. Ripe fruit processing accounts for 60% of whole fruit mass while 40% remains unutilized and generates waste (hard shell, pomace, fiber and seeds) on a massive scale which do not have high value applications. A new flavone 3,5,7-trihydroxy-2-(4′-hydroxy-3′-isopentyloxyphenyl-4<i>H</i>-chromen-4-one (<b>5</b>) in addition to the known compounds <b>1–4</b>, has been isolated from seeds of <i>A. marmelos</i>. Also, compound 7-(3′-methylbut-2′-enyloxy)-2<i>H</i>-chromen-2-one (<b>2)</b> has been isolated for the first time from <i>A. marmelos</i>. The structure of compounds <b>1–5</b> was determined by spectral analysis (UV, IR, NMR, etc.). Additionally, the non-edible oil obtained from seeds was investigated for waste to wealth recovery of 6-<i>O</i>-ascorbyl esters in high regioselectivity <i>via</i> one step semi-synthetic approach in the presence of ascorbic acid and H<sub>2</sub>SO<sub>4</sub> at ambient temperature.</p