Supplier Page from Thermo Fisher Scientific for Magnesium oxide, 98%, extra pure, powder, particle size: 99% <150 µm (-100 mesh)
4-Ethylaniline, 99+% from Thermo Fisher Scientific
Ethyl indole-2-carboxylate, 97% from Thermo Fisher Scientific
Ethyl picolinate, 99% from Thermo Fisher Scientific