Constituents of Eriobotrya japonica. A study of their antiviral properties.

The CHCl3 extract of Eriobotrya japonica from an Italian source was shown to contain four new triterpene esters, namely, 23-trans-p-coumaroyltormentic acid [1], 23-cis-p-coumaroyltormentic acid [2], 3-O-trans-caffeoyltormentic acid [3], and 3-O-trans-p-coumaroylrotundic acid [4], in addition to three common ursolic acid derivatives 5, 6, and 7. An investigation of the antiviral properties of compounds 1-7 revealed that only 3 significantly reduced rhinovirus infection. The compounds were ineffective towards human immunodeficiency virus type 1 (HIV-1) and Sindbis virus replication.