There is a little bit of interesting history connected with the melting point of harmaline. A report appeared that described an alkaloid from Peganum harmala that looked like harmaline but which melted 18 °C too high, and so it was thought to be an isomer and was given the name harmadine. This was all cleared up a few years later when it was observed that on an open melting point block, harmaline had a mp 242-244 °C (with beginnings of sublimation at 189 °C) and harmadine had the values of 241-243 °C and 178 °C. In a capillary tube, harmaline melted at 256°C and harmadine at 257 °C. So, harmadine is now a synonym for harmaline.