By Christian Holub
Updated December 02, 2015 at 07:12 PM EST
Peter Still/Redferns

Queen singer Freddie Mercury died of complications from AIDS in 1991, and now, rare audio of the iconic vocalist (from the sessions for his 1988 album Barcelona) have been included on a charity single for World AIDS Day, which took place Dec. 1.

Produced by Stuart Leathem, “Little Freddie Goes To School” matches singer Esther Trousdale with vocals from Mercury’s “When This Tired Old Body Wants to Sing” and a version of “The Golden Boy” to create a haunting, psychedelic effect. Listen above.

Proceeds from the single will go to the Mercury Phoenix Trust, the HIV/AIDS charity established by the surviving members of Queen in Mercury’s name. Hear the track below.