Complex sentence: His main surviving works are two large altarpieces, the first executed in oil for San Lorenzo Maggiore, probably commissioned about 1445 by Alfonso, which was dispersed in the Napoleonic period.
Split into simpler sentences: His main surviving works are two large altarpieces. The first was in oil for San Lorenzo Maggiore, probably commissioned about 1445 by Alfonso, which was dispersed in the Napoleonic period.