(+)-Araguspongine K InChI=1/C28H50N2O4/c31-28-17-8-4-3-7-13-24-15-20-29-19-9-12-23(26(29)33-24)11-5-1-2-6-14-25-16-22-30(32,21-10-18-28)27(28)34-25/h23-27,31H,1-22H2/t23-,24-,25-,26+,27+,28-,30?/m1/s