A compound having a structure of Formula I, is provided. In Formula I, X1-X7, Z1 and Z2 are each independently C or N; Z3 is selected from BR′, NR′, PR′, O, S, Se, C═O, S═O, SO2, CR′R″, SiR′R″, and GeRR″; L is selected from O, S, and NR; C1, C2, and C3 are all carbon atoms; the bonds represent single bond or double bond to fulfill the valency requirement of a neutral compound; each R1, R2, R3, R, R′, R″, RA, and RB is independently hydrogen or a substituent; and any two of R1, R2, R3, R, R′, R″, RA, and RB can be joined or fused together to form a ring. Further provided are OLEDs and related consumer products that utilize these compounds.