General Approach to Prostanes B₁ by Intermolecular Pauson–Khand Reaction: Syntheses of Methyl Esters of Prostaglandin B₁ and Phytoprostanes 16‐B₁‐PhytoP and 9‐L₁‐PhytoP

Abstract

A synthetic approach to the methyl esters of Prostaglandin B1 and Phytoprostanes 16‐B1‐PhytoP (PPB1‐I) and 9‐L1‐PhytoP (PPB1‐II) based on the modified Julia olefination of a formylcyclopentenone and an appropriately protected hydroxy sulfone has been developed. The cyclopentenones were efficiently prepared by intermolecular Pauson–Khand reaction of a (silyloxymethyl)alkyne. The sulfone counterpart was prepared by regioselective ring‐opening of the appropriate chiral epoxides by 2‐mercaptobenzothiazole. The protecting group for the alcohol functionality on the sulfone proved to be crucial. Protection as a tert‐butyl ether was the best solution, giving better results than a tert‐butyldimethylsilyl ether.

Structural/Functional Matches and Divergences of Phytoprostanes and Phytofurans with Bioactive Human Oxylipins

“…When analyzing the data reported in the literature on the profile and occurrence of PhytoPs and PhytoFs in the separate foods and food matrices, it is essential taking into consideration the evolution of the analytical instrumentation throughout the last years. Thus, regarding the detection methods used so far to identify and quantify PhytoPs and PhytoFs in plant matrices and complex biological systems, earlier reports have described different analytical approaches, such as gas chromatography coupled to mass spectrometry (GC–MS) [ 7 , 8 , 14 , 29 , 31 ], high-performance liquid chromatography (HPLC) coupled to a fluorescence detector [ 32 ], nuclear magnetic resonance of 1 H or 13 C [ 33 ], immunological approaches (Enzyme-Linked ImmunoSorbent Assay-ELISA) [ 34 ], and liquid chromatography coupled to mass spectrometry with tripe quadrupole technology (UHPLC-QqQ-MS/MS) [ 16 , 17 , 27 ]. Although the HPLC–UV analysis method is rapid, its sensitivity and specificity are not high enough to profile and quantify these compounds in complex matrices, especially in complex biological matrices, in which their concentration is frequently at the nanomolar, or even picomolar range.…”

New UHPLC–QqQ-MS/MS method for quantitative and qualitative determination of free phytoprostanes in foodstuffs of commercial olive and sunflower oils

“…Thus, a consequence to a greater exposure to ROS is that PhytoPs activate the expression of plant genes in response to stress which leads to higher protection of the plant to OS (Eckardt, 2008). For this reason, other authors have proposed that PhytoPs are not only excellent biomarkers of oxidative degradation of plant derived foodstuff but also biologically active molecules because they are components of an oxidant-injury-sensing, archaic signaling system that induces several plant defense mechanisms (Loeffler et al, 2005;Thoma et al, 2003;Vazquez-Romero, Verdaguer, & Riera, 2013). However, despite the physiological role found of PhytoPs in plants they are beginning to emerge as interesting compounds to be studied in the area of plant physiology.…”

Total syntheses of all tri-oxygenated 16-phytoprostane classes via a common precursor constructed by oxidative cyclization and alkyl–alkyl coupling reactions as the key steps

“…41 The total syntheses of ring-isomeric cyclopentenone PhytoP, namely 9-and 16-B 1 -and L 1 -PhytoP as well as 9-A 1 -and 9-J 1 -PhytoP, were accomplished by the Vidari-Zanoni group, 42,43 whereas Riera's group developed an individual approach to 16-B 1 -and 9-L 1 -PhytoPs. 44 A total synthesis of 16-D 1t -PhytoP was never accomplished. The only evidence for its occurrence stems from the transformation of a mixture of all possible F 1 -PhytoP isomers based on a procedure originally developed for an access to PGD 2 .…”