He was the son (possibly the eldest) of the "megas stratopedarches" John Synadenos, and brother of the "protostrator" Theodore Synadenos. He inherited the surname "Palaiologos" from his mother, Theodora Palaiologina Synadene, and was commonly referred to by it. He married a lady named Thomais, descended form the imperial dynasties of Laskaris and Palaiologos, although her exact parentage is unknown. No children of his are known. Very little is known about his life, except that he acted as an emissary of Andronikos III Palaiologos to his grandfather Andronikos II during the closing stages of the Byzantine civil war of 1321–1328, along with John Aplesphares.