Derek W. Murphy (born December 29, 1968),[2] better known as Sadat X, is an American rapper, best known as a member of alternative hip hop group Brand Nubian.

[7] At age 11, he and his parents moved to New Rochelle where he met future Brand Nubian bandmates Grand Puba and Lord Jamar.

In 1996, Sadat recorded on the Red Hot Organization's compilation CD America Is Dying Slowly, alongside Biz Markie, Wu-Tang Clan, Fat Joe and others.

The CD, meant to raise awareness of the AIDS epidemic among African American men, was called "a masterpiece" by The Source.

[12] In 1998, he and Brand Nubian released their fourth album Foundation[13] In 1999, he collaborated with Chicago-based rapper Common along with Talib Kweli on a Hi-Tek track-produced song called "One-Nine-Nine-Nine".

The album featured guest appearances from Ill Bill, Kurupt, A.G., Brand Nubian, Rhymefest and others, with production from Pete Rock, Diamond D, Buckwild, Sir Jinx, Will Tell and Dub Sonata.

In 2015, Sadat appeared in Mya Baker's documentary film Afraid of Dark which examined the experiences of Black men in America.