1-Phenyl-6,7-dihydroxy-isochroman suppresses lipopolysaccharide-induced pro-inflammatory mediator production in human monocytes.

Extra-virgin olive oil is an integral ingredient of the Mediterranean diet, and it has been suggested that its high consumption has beneficial effects on human health. Its protective effect, in particular against the development of CVD, has been related not only to the high content of oleic acid, but also to the antioxidant and anti-inflammatory properties of polyphenols. In order to verify the anti-inflammatory and anti-atherogenic properties of hydroxy-isochromans, a class of ortho-diphenols present in extra-virgin olive oil, we investigated the potential ability of 1-phenyl-6,7-dihydroxy-isochroman (L137) to modulate the production of key inflammatory mediators by human monocytes, by evaluating its in vitro effects on prostanoid (thromboxane A(2) and PGE(2)) and cytokine (TNF-α) production.

DDQ oxidation of hydroxyisochromans and homologues.

Some hydroxyisochromans and hydroxyphthalans are tested under oxidative conditions obtaining hydroxybenzophenone derivatives. All reactions were followed by (1)H NMR spectroscopy. Some final main oxidation products were also isolated and characterised.

An investigation on dihydroxy-isochromans in extra virgin olive oil.

Recently, some dihydroxy-isochromans were discovered in extra virgin olive oil. In this work, the authors tried to investigate whether these substances are natural compounds, present also in the olive fruit, or whether they are formed during the crushing and malaxation procedures, or during the subsequent storage of oil. The variation of dihydroxy-isochroman amounts during extra virgin olive oil ageing have also been investigated.

Synthesis of hydroxystilbenes and their derivatives via Heck reaction.

A group of differently substituted acetoxy- and methoxystilbenes were synthesised via Heck reaction. A comparison between the use--as coupling reagents--of iodobenzene derivatives and diazonium salts was performed. A successful microwave-assisted demethylation by pyridine hydrochloride of some methoxystilbenes was carried out.

An improved synthesis of resveratrol.

In this article we report an improved total synthesis of resveratrol, increasing the overall yield from 22 to 71%. The synthesis reported in our previous publication was made up of two fundamental steps: a Wittig reaction and a Heck coupling. Here we studied these steps separately to increase the individual yields.

Highlights in oleuropein aglycone structure.

Oleuropein hydrolysis products, obtained both by endogenous beta-glucosidase and almond commercial one, were investigated by classic methodologies and by 1HNMR experiments. We found that both presence and relative amount of the different compounds in the reaction mixture are stricly related to the used enzyme.

A new diacylglycerol from fresh olive pulp.

The isolation from olive pulp of a diacylglycerol showing an oleic as well as an elenoic acid residue, the latter probably derived from a natural enzymatic oleuropein hydrolysis, is reported. The given structure is supported by 1H- and 13C-NMR data.

Olive oil isochromans inhibit human platelet reactivity.

The effects of certain polyphenolic compounds in red wine, such as resveratrol and quercetin, have been widely investigated to determine the relationship between dietary phenolic compounds and the decreased risk of cardiovascular diseases. However, the effects of polyphenolic compounds contained in other foods, such as olive oil, have received less attention and little information exists regarding the biological activities of the phenol fraction in olive oil. The aim of this study was to evaluate the antiplatelet activity and antioxidant power of two isochromans [1-(3'-methoxy-4'-hydroxy-phenyl)-6,7-dihydroxy-isochroman (encoded L116) and 1-phenyl-6,7-dihydroxy-isochroman (encoded L137)] recently discovered in olive oil and synthesized in our laboratory from hydroxytyrosol.