Lysergic acid 2-butyl amide (2-Butyllysergamide, LSB) is an analogue of LSD originally developed by Richard Pioch at Eli Lilly in the 1950s,[2] but mostly publicised through research conducted by the team led by David E. Nichols at Purdue University.

The corresponding (R)-2-pentyl analogue has higher binding affinity for the 5-HT1A and 5-HT2A receptors, but is less potent in producing drug-appropriate responding, suggesting that the butyl compound has a higher efficacy at the receptor target.

The main use for this drug has been in studies of the binding site at the 5-HT2A receptor through which LSD exerts most of its pharmacological effects,[5] with the stereoselective activity of these unsymmetric monoalkyl lysergamides foreshadowing the subsequent development of compounds such as lysergic acid 2,4-dimethylazetidide (LSZ).

Morning glory: Argyreia nervosa (Hawaiian Baby Woodrose), Ipomoea spp.

(Morning Glory, Tlitliltzin, Badoh Negro), Rivea corymbosa (Coaxihuitl, Ololiúqui)