It was discovered that the reaction of vitamin D₃ with Nield reagent yielded two new compounds, bisteroid A (mp 76-78°) and bisteroid B (mp 98-100°). The molecular formula of bisteroid A was confirmed to be C₅₄H₈₄ and bisteroid B was confirmed to be a monoacetate having the molecular formula C₅₆H₈₈O₂. The chemical structures of bisteroids A and B were studied and assumed structures were given for them.