Endogenous central calcitonin (CT) receptor agonist that stimulates cAMP formation at a potency 350-fold greater than CT (ED50 values are 0.2 and 71 nM respectively). Displays no activity at calcitonin-gene related peptide (CGRP) and adrenomedullin receptors. Inhibits formation of multinuclear osteoclasts with similar efficacy to CT in vitro. Suppresses food intake and increases body temperature in free-feeding rats, and significantly decreases plasma calcium levels in vivo.

The young fruits of Citrus grandis.

Clemastanin B has antioxidant and anti-inflammatory activities, it exerts its anti-influenza activity by inhibiting the virus multiplication, prophylaxsis and blocking the virus attachment.