Sammi Tesfazgi, 21, of Lithos Road, West Hampstead was jailed for life, a 16-year-old was sentenced to 20 years, both for murder, while Rilind Tahiri, 22, of North Road, Holloway, was sentenced to 14 years for manslaughter of Yasir Beshira.
Metropolitan Police were called at 5.20pm on December 8, 2016, after a man collapsed in Netherwood Street in Hampstead, having suffered a gunshot wound to the stomach.
The London Ambulance Service attended to Yashir, who was also being tended to by members of the public, but he died at the scene.
Prior to the shooting Yasir had been in Palmerston Road where he was approached by a lone male who we now know to have been the 16-year-old, who then shot Yasir and immediately fled the scene on foot along Palmerston Road and into the Webheath Estate.
The 16-year-old had been driven to the scene in a stolen car by Tahiri and Tesfazgi, who then waited for him to return before driving him away.
Following this Tahiri set fire to the car to destroy evidence.
DCI Andy Partridge said: "This shocking attack was carried out during rush hour in a very busy residential location. I want to thank those members of the public who came forward to try and save Yasir after he was shot and those who greatly assisted the police investigation.
"This was a complex and protracted investigation. These sentences should remind those planning such violent attacks on our streets that they will be pursued and brought to justice for their actions."
Enquiries identified the gun used had been linked to a non-fatal shooting in Camden on in September 2016, and a knife which was also recovered from that scene was forensically linked to Tesfazgi.
Two others were sentenced for assisting an offender: Ashley McFarland, 35, of Hertford. was sentenced to five years and Kim McFarland, 59, of Belsize Park, was sentenced to three years.
All were sentenced at the Old Bailey on November 27.