Chemical constituents from L. (Boraginaceae) and their antibacterial activity.

Chemical investigation of L. (Boraginaceae) resulted in the isolation of the following ten known compounds: 1-naphthaleneacetic-5-carboxy-1,2,3,4,4a,7,8,8a-octahydro-1,2,4a-trimethyl-[1-(1,2, 4a,8a)]-acid (), hexacosanoate-1-glyceryl (), 3-urs-12,20(30)-diene-27,28-dioic acid (), 3-D-glucopyranosylurs-12,20(30)-diene-27,28-dioic acid (), stigmasterol (), stigmasterol-3---D-glucopyranoside (), oleanolic-acid (), 3--acetyl-oleanolic acid (), betulin () and spinasterol-3--D-glucopyranoside (). The isolated compounds were characterised by using spectroscopic methods, 1D and 2D NMR, mass spectroscopy (ESI-MS) and by comparison with the literature data. To the best of our knowledge, compounds , , , and were isolated for the first time from the genus. This result improves the chemotaxonomy knowledge of the genus. The antibacterial activities were performed by the Muller-Hinton agar diffusion method. The antibacterial activities were studied on , , , and ATCC 25922. Compounds and , at 20.0 mg/mL resulted to be effective antimicrobial against , and