Synthesis of Conjugated Dienes in Natural Compounds

This review describes the various synthetic methods commonly used to obtain molecules possessing conjugated dienes. We focus on methods involving cross-coupling reactions using various metals such as nickel, palladium, ruthenium, cobalt, cobalt/zinc, manganese, zirconium, or iron, mainly through examples that aimed to access natural molecules or their analogues. Among the natural molecules covered in this review, we discuss the total synthesis of a phytohormone, Acid Abscisic (ABA), carried out by our team involving the development of a conjugated diene chain.

Optimisation of Healthy-Lipid Content and Oxidative Stability during Oil Extraction from Squid (Illex argentinus) Viscera by Green Processing

Green extraction was applied to Argentinean shortfin squid (Illex argentinus) viscera, consisting of a wet pressing method including a drying step, mechanic pressing, centrifugation of the resulting slurry, and oil collection. To maximise the oil yield and ω3 fatty acid content and to minimise the oil damage degree, a response surface methodology (RSM) design was developed focused on the drying temperature (45–85 °C) and time (30–90 min). In general, an increase of the drying time and temperature provided an increase in the lipid yield recovery from the viscera. The strongest drying conditions showed a higher recovery than 50% when compared with the traditional chemical method. The docosahexaenoic and eicosapentaenoic acid contents in the extracted oil revealed scarce dependence on drying conditions, showing valuable ranges (149.2–166.5 and 88.7–102.4 g·kg−1 oil, respectively). Furthermore, the values of free fatty acids, peroxides, conjugated dienes, and ω3/ω6 ratio did not show extensive differences by comparing oils obtained from the different drying conditions. Contrary, a polyene index (PI) decrease was detected with increasing drying time and temperature. The RSM analysis indicated that optimised drying time (41.3 min) and temperature (85 °C) conditions would lead to 74.73 g·kg−1 (oil yield), 1.87 (PI), and 6.72 (peroxide value) scores, with a 0.67 desirability value.

PSIX-9 Effect of calcium nitrate fed to dairy cows on nitrate residues, fatty acids profile, and antioxidant capacity in milk

Six lactating cows (106.3 ± 14.8 DIM; 550.7 ± 21.8 kg BW) were enrolled in a replicated 3 × 3 Latin square to evaluate the supplementation of double salt of calcium ammonium nitrate decahydrate (CAN), composed by 16.5% N, 76.5% of nitrate (NO3 -), and 85.0% DM, on NO3 - and nitrite (NO2 -) residues, fatty acids (FA) proportion, and antioxidant capacity in milk. Each period lasted 21 d, with 14 d for adaptation and 7 d for sampling. Treatments were URE (11.9 g/DM of urea as a control), CAN15: 15 g of CAN (11.5 g of NO3 - on DM), and CAN30: 30 g of CAN (23 g of NO3 - on DM). Milk samples were collected on d 15–16 of each period, frozen at –20°C, and after analyzed for NO3 - and NO2 - residues, fatty acids, and antioxidant capacity. Data were analyzed using PROC MIXED of SAS. Supplemental CAN increased by 26% NO3 - residue in milk (P = 0.02), whereas did not affect (P < 0.05) NO2 - concentration (average of 0.042 mg/L). Total CLA and short-chain FA were not affected (P > 0.05) by CAN. Medium-chain FA decreased linearly (P < 0.05), while long-chain FA (P = 0.06) and monounsaturated FA (P = 0.08) tended to increase linearly. Saturated FA reduced (P < 0.05) linearly; however, the total of polyunsaturated FA was not affected (P > 0.05). There were no effects of CAN (P > 0.05) on n-3, n-6, and n-6/n-3 ratio. Milk reducing power and TBARS concentration were not affected (P > 0.05) by CAN, whereas conjugated dienes increased (P = 0.02) linearly (URE= 47.6 vs. CAN15= 52.7 vs. CAN30= 63.4 mmol/kg of fat). Supplementing CAN at 30 g/DM reduced total saturated FA and increased conjugated dienes, caused possibly by lower rumen biohydrogenation, which might increase lipid oxidation in milk.

A Dual CuH- and Pd-Catalyzed Stereoselective Synthesis of Highly Substituted 1,3-Dienes

Conjugated dienes are versatile building blocks and prevalent substructures in synthetic chemistry. Herein, we report a method for the stereoselective hydroalkenylation of alkynes, utilizing readily available enol triflates. We leveraged an in situ generated and geometrically pure vinyl-Cu(I) species to form the Z,Z- or Z,E-1,3-dienes in excellent stereoselectivity and yield. This approach allowed for the synthesis of highly substituted Z-dienes, including pentasubstituted 1,3-dienes, which are difficult to prepare by existing approaches.

Chronic and moderate consumption of reduced-alcohol wine confers cardiac benefits in a rat model of pulmonary arterial hypertension

Objectives In pulmonary arterial hypertension (PAH), right ventricular (RV) dysfunction develops via mechanisms involving oxidative stress. Moderate and chronic red wine (RW) consumption reduces oxidative stress and confers cardioprotection but its effect on PAH is unknown. We evaluated whether moderate and chronic consumption of reduced-alcohol RW (RARW) confers cardioprotection in a monocrotaline (MCT)-induced PAH rat model. Results Rats were randomly grouped: control; MCT; RARW; MCT + RARW. Wine was diluted to mimic moderate intake for humans, and consumed from 7 days before, until 28 days after MCT-injection. Echocardiography measured pulmonary artery acceleration time (PAAT) and RV thickness. Conjugated dienes (CD), and thiobarbituric acid reactive substances (TBARS) concentrations were assessed. MCT induced RV thickness and decreased PAAT compared to controls [1.22 ± 0.09 mm vs 0.46 ± 0.02 mm and 14 ± 1 vs 23 ± 2 m/s, respectively (p < 0.001)]. Chronic RARW consumption limited MCT-induced RV hypertrophy and increased PAAT. CD and TBARS increased in MCT-treated animals compared to controls (672 ± 43 nmol/L vs 453 ± 35 nmol/L; p < 0.01 and 13 ± 2 µmol/L vs 4 ± 0.3 µmol/L; p < 0.01). RARW reduced MCT-induced CD (472 ± 27 nmol/L vs 672 ± 43 nmol/L; p < 0.01). Conclusion Chronic and moderate intake of RARW ameliorates MCT-induced PAH in rats, which may be partly attributable to reduction of lipid peroxidation.