What is the name of Isaac Asimov's first full novel?

"Pebble in the Sky" (1950) was Asmov's first novel.

Isaac Asimov (1920-1992) was born in Russia but his family moved to the USA when he was just three. Aside from his writing prowess, he was also a professor of biochemistry at Boston University. Along with Robert A. Heinlein and Arthur C. Clarke, Asimov was known as one of the "Big Three" writers of science fiction.

"Pebble in the Sky" was originally called "Grow Old with Me", but Asimov extended the length at his publisher's request.

https://wiki2.org/en/Pebble_in_the_Sky+Newton