You are starting off well by looking at what has already been found in these plants....please note the references below which list compounds already found in this group.

http://www.academicjournals.org/article/article1380528747_Sharma%20et%20al.pdf

http://www.uni-heidelberg.de/institute/fak14/ipmb/phazb/pubwink/1999/3.%201999.pdf

http://www.hygeiajournal.com/downloads/13035980963.amutha%20final%20GC.pdf

the family is characterized by the presence of pyrrolizidinic alkaloids. they are often observed under N-oxide forms.

In terms of polysaccharides, the family is curious in two ways -- the Borages are one of the five or six families worldwide with fructans (i.e. fructose polymers built on a sucrose backbone). Also, I did some hydrolytic treatments of bark and stem-wood from Cordia spp., a fast-growing tropical member of the family, and was struck by the unusual Arabinose-rich  neutral-sugar profile. So little work has been done on tree storage polysaccharides, I'd not be surprised if some components were potentially mobile reserves. I can send you the profiles if they are of interest.  

yes,thank you Dr. Ted

Previously many publications have been reported in connection with compounds from Boraginaceae family plants. Even, Sharma et al., 2009 discussed deeply in his review article (Jack Silver quoted already). So, you will select or isolate compound from Boraginaceae family plants as per your further application.

I don't know the composition of all borraginaceae, but for Alkanna tinctoria Tausch., it contain in the root the naphtoquinones pigments, un group of phenolic compounds a several species of borraginaceae.  the most important is alkannin and other esters of the alkannin. The root also contain  cerotinic  acid and carnaubic alcohol.

generally in the stem and roots you will find tannins, cellulose, glucose binds to secunder metabolites (terpenes or alkaloids)