Four lignans, boehmenan H {2-(4-hydroxy-3-methoxyphenyl)-5-[3-(4-hydroxy-3-methoxycinnamoyloxy)propyl] -3-hydroxymethyl-7-methoxybenzodihydrofuran}, boehmenan K {2-(4-hydroxy-3-methoxyphenyl)-5-[3-(4-hydroxycinnamoyloxy)-1-propenyl]-3-(4 -hydroxy-3-methoxycinnamoyloxymethyl)-7-methoxybenzodihydrofuran}, threo-carolignan H {threo-1-(4-hydroxy-3-methoxyphenyl)-2-{4-[3-(4-hydroxy-3-methoxycinnamoylox y)propyl]-2-methoxyphenoxy}-1,3-propanodiol}, and threo-carolignan K {threo-1-(4-hydroxy-3-methoxyphenyl)-3-(4-hydroxy-3-methoxycinnamoyloxy)-2-{ 4-[3-(4-hydroxycinnamoyloxy)-1-propenyl]-2-methoxyphenoxy}-1-propanol} as well as several other lignans, aldehydes and a tyramine derivative were isolated from the acetone extract of core of kenaf (Hibiscus cannabinus). All the structures were established by spectroscopic methods. The hitherto unreported 1 3 C NMR spectra of some compounds are also presented and discussed. 2D NMR techniques have allowed the revision of certain previously reported 1 3 C NMR assignments of some scarce naturally occurring compounds.