The Nobel Prize in chemistry has been awarded to Benjamin List and David W.C. MacMillan, two scientists honored for creating “an ingenious tool for building molecules” that helped develop new drugs and made chemistry greener.

The pair were awarded the prize “for the development of asymmetric organocatalysis.” Their discoveries “initiated a totally new way of thinking for how to put together chemical molecules,” said Pernilla Wittung-Stafshede, a member of the chemistry Nobel committee.

“This new toolbox is used widely today, for example in drug discovery, and in fine chemicals production and is already benefiting humankind greatly,” Wittung-Stafshede added.

German scientist List and Scottish chemist MacMillan worked independently of each other but share the prize, the third Nobel award to be handed out this week.