6831-10-3 Amaralin from helenium amarum NSC 285242 Oxireno(1,2)azuleno(6,5-b)furan-5(1aH)-one, decahydro-8-hydroxy-2,7a-dimethyl-6-methylene-, (1aR-(1aalpha,1bbeta,2beta,3aalpha,6abeta,7aalpha,8alpha,8aalpha))-