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Kallaganti Rama V S Krishna - One of the best experts on this subject based on the ideXlab platform.
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the first stereoselective total synthesis of the Z Isomer of 6s 7r 9r 6 7 dihydroxy 9 propylnon 4 eno 9 lactone
RSC Advances, 2013Co-Authors: Palakodety Radha Krishna, Sunchu Prabhakar, Kallaganti Rama V S KrishnaAbstract:The first stereoselective total synthesis of the Z-Isomer of (6S,7R,9R)-6,7-dihydroxy-9-propylnon-4-eno-9-lactone involving Sharpless titanium(IV) mediated regioselective ring-opening reaction, Steglich esterification and RCM as the key steps is reported.
Biswanath Das - One of the best experts on this subject based on the ideXlab platform.
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chiral approach to total synthesis of phytotoxic and related nonenolides Z Isomer of 6s 7r 9r 6 7 dihydroxy 9 propylnon 4 eno 9 lactone herbarumin iii and their c 9 epimers
Tetrahedron, 2016Co-Authors: Lingaiah Maram, Raghavendar Reddy Parigi, Biswanath DasAbstract:Abstract A new and efficient strategy has been developed for the stereoselective total synthesis of nonenolides: (Z)-Isomer of (6S,7R,9R)-6,7-dihydroxy-9-propylnon-4-eno-9-lactone, herbarumin-III and their C-9 epimers starting from d (−) ribose. The synthesis includes the coupling of the alcohol and acid fragments of the molecules, employing Yamaguchi esterification protocol followed by intramolecular ring closure metathesis. The method has efficiently constructed the 10-membered lactone skeleton of the compounds with proper stereogenic centers containing appropriate functionalities.
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stereoselective total synthesis of the Z Isomer of a novel phytotoxic nonenolide from phomopsis sp hccb03520 and its c 6 epimer
Tetrahedron Letters, 2014Co-Authors: Cheruku Ravindra Reddy, Biswanath DasAbstract:Abstract The ( Z )-Isomer of a phytotoxic nonenolide, (6 S ,7 R ,9 R )-6,7-dihydroxy-9-propylnon-4-eno-9-lactone isolated from Phomopsis sp. HCCB03520 and its C-6 epimer have been synthesiZed through a common route starting from butyraldehyde. The synthesis involves enantioselective Maruoka allylation, Sharpless asymmetric epoxidation and intramolecular ring closing metathesis as the important steps.
Masaki Honda - One of the best experts on this subject based on the ideXlab platform.
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Z-Isomers of Astaxanthin Exhibit Greater Bioavailability and Tissue Accumulation Efficiency than the All-E-Isomer.
Journal of agricultural and food chemistry, 2021Co-Authors: Masaki Honda, Kazuya Murakami, Yukiko Osawa, Yuki Kawashima, Kazuaki Hirasawa, Ikuo KurodaAbstract:The purpose of the present study was to clarify the differences in the bioavailability and tissue accumulation efficiency between (all-E)- and (Z)-astaxanthin. Astaxanthin with a high proportion of the Z-Isomer (especially rich in the 9Z- and 13Z-Isomers) was prepared from (all-E)-astaxanthin by thermal treatment and solid-liquid separation. The all-E-Isomer- or Z-Isomer-rich diet was fed to male rats for 2 weeks. After the feeding period, blood and tissue samples were collected, and their astaxanthin levels were evaluated. The Z-Isomer-rich astaxanthin diet resulted in higher levels of astaxanthin in blood and many tissues (in particular, skin, lung, prostate, and eye) compared to the all-E-Isomer-rich diet. Moreover, the Z-Isomer-rich diet enhanced the level of the 13Z-Isomer in blood and tissues rather than that of the 9Z-Isomer. These results strongly supported that astaxanthin Z-Isomers have greater bioavailability and tissue accumulation efficiency than the all-E-Isomer. Moreover, (13Z)-astaxanthin would have higher bioavailability and tissue accumulation than the other Isomers.
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astaxanthin Z Isomer rich diets enhance egg yolk pigmentation in laying hens compared to that in all e Isomer rich diets
Animal Science Journal, 2021Co-Authors: Masaki Honda, Yuki Kawashima, Kazuaki Hirasawa, Takeshi Uemura, Jinkun Sun, Yoshiaki HayashiAbstract:The effects of feeding diets containing astaxanthin with different Z-Isomer ratios to laying hens on egg qualities, such as astaxanthin concentration in egg yolk and yolk color, were investigated. As the astaxanthin source, a natural microorganism Paracoccus carotinifaciens was used. Astaxanthin with different Z-Isomer ratios was prepared by thermal treatment with different conditions and then added to the basal diet at a final astaxanthin concentration of 8 mg/kg. We found that, as the Z-Isomer ratios of astaxanthin in the diet increased, the astaxanthin concentration in egg yolk and the yolk color fan score also increased significantly. Importantly, feeding a 50.6% Z-Isomer ratio diet increased astaxanthin concentration in egg yolk by approximately fivefold and the color fan score by approximately 2 compared to that in hens fed an all-E-Isomer-rich diet. Moreover, we showed that feeding Z-Isomer-rich astaxanthin to laying hens increased plasma astaxanthin concentration by more than five times in comparison to that in hens fed an all-E-Isomer-rich diet. These results indicate that Z-Isomers of astaxanthin have higher bioavailability than that of the all-E-Isomer and thus they exhibit greater egg yolk-accumulation efficiency.
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one step preparation of Z Isomer rich β carotene nanosuspensions utiliZing a natural catalyst allyl isothiocyanate via supercritical co2
Symmetry, 2020Co-Authors: Yelin Zhang, Tetsuya Fukaya, Masaki Honda, Hideki Kanda, Motonobu GotoAbstract:This study aims to improve the production efficiency of β-carotene suspensions using a naturally occurring Z-IsomeriZation-accelerating catalyst, allyl isothiocyanate (AITC), via supercritical CO2 (SC-CO2). Namely, utiliZing solubility improvement of β-carotene with the Z-IsomeriZation by adding AITC in the SC-CO2-used dispersion process, the encapsulation efficiency of β-carotene was enhanced. The dispersion of β-carotene was conducted by ultrasonic treatment, and there was no involvement of organic solvents in the whole process. When 100 mg of AITC was added in the dispersion process, the encapsulation efficiency (β-carotene content in resulting suspension) was approximately 3.5 times higher than that without addition of the catalyst. Moreover, the Z-Isomer ratio of β-carotene in the suspensions significantly improved, that is, it was approximately 12 times higher than the raw β-carotene material. Since Z-Isomers of β-carotene are known to have higher antiatherosclerotic and antiatherogenic activities compared to the all-E-Isomer, this one-step method not only efficiently produces β-carotene suspensions without organic solvents but also enhances the bioactivities of them.
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impact of global traditional seasonings on thermal Z IsomeriZation of all e lycopene in tomato puree
Lwt - Food Science and Technology, 2019Co-Authors: Masaki Honda, Tetsuya Fukaya, Kohei Ichihashi, Yelin Zhang, Takashi Hibino, Hakuto Kageyama, Motonobu GotoAbstract:Abstract The aim of this work was to investigate the effects of commercially available global traditional seasonings on the thermal Z-IsomeriZation of tomato lycopene. On heating at 80 °C for 1 h, the total Z-Isomer content of lycopene present in tomato puree containing 5% olive oil increased from 5.5% to 32.3%. When several seasonings were individually added to the mixture of tomato puree and 5% olive oil, the thermal Z-IsomeriZation of lycopene was significantly increased. For instance, when 10% jerk sauce, tapenade, and Dijon mustard were added to the tomato mixture, the total Z-Isomer content following heating increased to 58.7%, 50.2%, and 47.3%, respectively. The results indicated that certain food ingredients like escallion (Allium fistulosum L.), caper (Capparis spinosa L.), and mustard (Brassica juncea L.) have a Z-IsomeriZation promoting effect. In addition, when heating was performed in the absence of those seasonings, the 13Z-Isomer was mainly increased. On the other hand, in the presence of the above seasonings, the 5Z-Isomer, which has higher functionality and storage stability than other Z-Isomers, was significantly increased. Our finding that some seasonings have a Z-IsomeriZation promoting effect is applicable to the production of tomato-based dishes containing higher proportions of lycopene Z-Isomers, which have greater bioavailability.
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Z-Isomers of lycopene exhibit greater liver accumulation than the all-E-Isomer in mice
Bioscience Biotechnology and Biochemistry, 2019Co-Authors: Masaki Honda, Yuki Nakayama, Sho Nishikawa, Takanori TsudaAbstract:ABSTRACTThe effect of oral administration of all-E-Isomer-rich and Z-Isomer-rich lycopene on liver accumulation in mice was investigated. When a diet rich in the Z-Isomers was administered for 4 we...
Palakodety Radha Krishna - One of the best experts on this subject based on the ideXlab platform.
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the first stereoselective total synthesis of the Z Isomer of 6s 7r 9r 6 7 dihydroxy 9 propylnon 4 eno 9 lactone
RSC Advances, 2013Co-Authors: Palakodety Radha Krishna, Sunchu Prabhakar, Kallaganti Rama V S KrishnaAbstract:The first stereoselective total synthesis of the Z-Isomer of (6S,7R,9R)-6,7-dihydroxy-9-propylnon-4-eno-9-lactone involving Sharpless titanium(IV) mediated regioselective ring-opening reaction, Steglich esterification and RCM as the key steps is reported.
Soon Hyeok Hong - One of the best experts on this subject based on the ideXlab platform.
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highly regioselective and e Z selective hydroalkylation of ynone ynoate and ynamide via photoredox mediated ni ir dual catalysis
Organic Letters, 2018Co-Authors: Geun Seok Lee, Soon Hyeok HongAbstract:Exclusively α- and highly E/Z-selective hydroalkylation of ynone, ynoate, and ynamide was achieved via photoredox mediated Ni/Ir dual catalysis with high atom and step economy, producing trisubstituted enones, which are versatile synthetic building blocks. The developed reaction selectively delivered the α/Z Isomer, which is complementary to the previously reported β-alkylation processes. The trisubstituted enones could be transformed to more valuable compounds via post-functionaliZation.
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Highly Regioselective and E/Z‑Selective Hydroalkylation of Ynone, Ynoate, and Ynamide via Photoredox Mediated Ni/Ir Dual Catalysis
2018Co-Authors: Geun Seok Lee, Soon Hyeok HongAbstract:Exclusively α- and highly E/Z-selective hydroalkylation of ynone, ynoate, and ynamide was achieved via photoredox mediated Ni/Ir dual catalysis with high atom and step economy, producing trisubstituted enones, which are versatile synthetic building blocks. The developed reaction selectively delivered the α/Z Isomer, which is complementary to the previously reported β-alkylation processes. The trisubstituted enones could be transformed to more valuable compounds via post-functionaliZation
