Andrew Surman had curled a left-footed opener for the Cherries after six minutes but despite a string of fine chances, they could not build on the lead.
Souleymane Doukara equalised with a calm finish on 66 minutes, centre-back Bellusci sent a stunning long range free-kick into the top corner a quarter of an hour later, while Antenucci rounded things off.
Bournemouth would have been ahead earlier but for a wonder save from goalkeeper Marco Silvestri, who tipped a curling Ryan Fraser shot around the post after two minutes.
Neil Redfearn named four Italians in his starting line-up but Silvestri could do nothing about former England Under-21 international Surman’s first goal since re-signing on transfer deadline day.
After Surman’s strike, Eddie Howe’s men went in search of number two in a bid to try and avoid any last-minute mishaps, such as the one they suffered against Rotherham at the weekend.
Matt Ritchie had a shot saved down low by Silvestri and only some frantic last-ditch defending kept the lively Callum Wilson from letting fly in the box.
After Ritchie had forced Silvestri into a fingertip save from his spectacular 30-yard drive, Wilson had the chance to bag his fifth of the season after 25 minutes.
The former Coventry striker won the leg race with Jason Pearce but after taking it past Silvestri once to leave the goal gaping, the keeper dived at his feet to stop the danger.
It took half-an-hour before the away side finally started to see some of the ball but they were struggling to get the final pass into the reliable Billy Sharp.
While owner Massimo Cellino may be in favour of former Leeds midfielder and ex-Argentina boss Alejandro Sabella to take over at Elland Road, Redfearn fired his side up for the second half.
The visitors enjoyed a spell in their opponents half and after Andy D’Urso had turned away strong penalty appeals at each end, got their deserved equaliser after Doukara finished from Tommaso Bianchi’s pass.
Moments later former Southampton man Sharp picked the ball up just outside the centre circle and galloped at the heart of the defence but dragged his shot inches wide with Camp stranded.
Neither team were settling for a point and introduced attacking substitutions to go for the three points.
And it was the Leeds fans who went home ecstatic with the two rapid goals completing a deserved victory.
Bellusci’s 30-yard free-kick flew into the top corner and left Lee Camp helpless.
And after the wonder-strike, the stage was set for Antenucci to pick up on a Doukara through ball and round off a well-deserved second win in three games for the Yorkshire outfit.