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We report here an updated summary about iridoid composition of a series from the genus Scrophularia which have been investigated until now from a phytochemistry point of view. In addition a list is included about iridoids isolated in our laboratory from different plant parts of Scrophularia scorodonia L.,which are compared with iridoids from some species of the Scrophularia genus. The present study may serve as a current information to researchers working on phytochemistry and pharmacological aspects from the Scrophularia genus and possibly to serve as a new starting point for future investigations

Catalpol ( 1 ), harpagoside ( 2 ), aucubin ( 3 ), 10-benzoylcatalpol ( 4 ) and 6-a-hydroxy-geniposide ( 5 ) were isolated from the aerial parts of Plantago lagopus L. for the first time. More generally, this is the first report of compound 5 being obtained from a plant extract.

A new sulfated triterpene glycoside with the sulfate group located in an unusual position in the carbohydrate moiety, was isolated from the MeOH extract of the aerial parts of Bupleurum rigidum. This compound was identified by a combination of chemical degradation and spectral methods as 3beta,16beta,23-trihydroxy-13, 28-epoxyolean-11-en-3beta-yl-beta-D-glucopyranosyl-(1-->2)[4-sulfate- beta-D-glucopyranosyl-(1-->3)]-beta-D-fucopyranoside (sandrosaponin I) (1). In addition, the known compound 3beta,16beta, 23-trihydroxy-13, 28-epoxyolean-11-en-3beta-yl-beta-D-glucopyranosyl-(1-->2)[beta-D-glu copyranosyl-(1-->3)]beta-D-fucopyranoside (2) was isolated in the present investigation.

Both the aerial parts and the roots of Bupleurum rigidum L. subsp. Rigidum have been thoroughly investigated. From the BuOH extract of the aerial parts of B. rigidum an already known and six new saponins have been isolated and their structures have been studied by Ms, IR and NMR spectroscopy and chemical degradations. Six of them are related to saikogenin F and one to saikogenin D. They were given the trivial namesof sandrosaponins I-VI. All bore a trisaccharide moiety, namely β- D-Glcp(l→2)[β-D-Glcp(l→)]β-D-Fucp, in which the second Glcp unit was sulphated at position O-4, in all the compounds but one (buddlejasaponin IV). From the roots of B. rigidum five new saponins have been isolated and identified, of which three were saikosaponins, two related to saikogenin F andone to saikogenin D. One of them was also found in the aerial parts. Two saponins were related to oleanolic acid. Trivial names of sandrosaponins VII-X were given to them. Additional compounds also isolated and identified were two acetylenic derivatives (falcarinol and diynene) and a phenolic glycoside (osmantolide). Buddlejasaponin IV and sandrosaponin I present a potent in vivo antiinflamatory effect on mouse ear edema induced by phorbol myristate acetate (PMA). The effects of these compounds on swelling and other inflamatory parameters are described. In screening for in vitro effects of thosesaikosaponins on cellular systems generating cyclooxygenase (COX)and lipooxygenase (LOX)metabolites, most saikosaponins showed a significant effect. The action is more marked on LOX metabolite LTC4.

As a part of our studies on the biologically active substances from Spanish plants, we have undertaken an investigation of the chemical constituents of a typical mediterranean species, Phillyrea latifolia L. (Oleaceae). Two secoiridoid glycosides, three phenylpropanoid glycosides, one lignane and two triterpenic acids were isolated from the leaves of this species and identified. The phytochemical analysis of the aerial parts of P. latifolia revealed that it is a rich source of oleuropeoside.

Three phenylpropanoid glycosides (salidroside, syringin and coniferin) and one lignan (phillyrin) isolated from the leaves of Phillyrea latifolia L. (Oleaceae) were tested for interactions with the cyclo-oxygenase and 5-lipoxygenase pathways of arachidonate metabolism in calcium-stimulated mouse peritoneal macrophages and human platelets, and for their effects on cell viability. These compounds are capable of exerting inhibitory actions on enzymes of the arachidonate cascade. Phillyrin, salidroside and syringin exert a preferential effect on the cyclo-oxygenase pathway, inhibiting release of the cyclo-oxygenase metabolites prostaglandin E2 (IC50 values 45.6 microM, 72.1 microM and 35.5 microM, respectively) and to a lesser extent reducing thromboxane B2 levels (IC50 values 168 microM, 154 microM and 29.3 microM, respectively). In contrast, coniferin can be classified as a "dual inhibitor", since it produces reduction in generation of both cyclo-oxygenase (IC50 values 75.2 microM for prostaglandin E2 and 619 microM for thromboxane B2) and 5-lipoxygenase metabolites, but the effects are greater against leukotriene C4 (IC50 value 63.6 microM). Structure-activity relationships of the three phenylpropanoid glycosides are discussed. Thus, like some other compounds found in medicinal herbs, our molecules possess an array of potentially beneficial anti-eicosanoid properties which may, alongside other constituents, contribute to the claimed therapeutic properties of the plant from which they are derived.

In the present study we report the isolation of a phenylpropanoid glucoside, plantamajoside, together with rosmarinic acid, chlorogenic acid and luteolin-7-O-monoglucoside. This is the first report of these compounds from Plantago lagopus.

Seasonal variations on the content of harpagoside in Scrophularia scorodonia L. (Scrophulariaceae) were investigated using plants collected monthly from January to December in 1995. During growth of this species the percentage of harpagoside was the highest during the maxim um development of the plant, specially in July. H arpagoside levels differed among leaves, stems and flowers of S. scorodonia. Leaves were distinguished from other plant parts by higher levels of harpagoside. Drying at ambient temperature influenced the yield of harpagoside com pared with the results of plant drying by microwave.