Dipankar, a 10th tee starter, played a bogey-free round as he collected two birdies on back-nine before adding three more on the front-nine.
Mumbai-based amateur Shivam Ashok Tibrewal occupied second place at two-under 70. Tibrewal had five birdies, a bogey and a double-bogey in his round.
Delhi's Ikramuddin Shah fired an even-par 72 to be placed third.
The top 39 players (+ ties) will qualify from Pre Qualifying I, a 36-hole event, for the Final Qualifying Stage.