1,3-Diphenylbut-2-en-1-one,
PhC(=O)CH=C(CH3)Ph, and its ring-substituted derivatives.
Source:
PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1333 (https://doi.org/10.1351/pac199567081307)