- Enzymatic liberation of lycotetraose from the Solanum glycoalkaloid α-tomatine
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The branched tetrasaccharide, O-β-D-glucopyranosyl-(1→2)-O- [β-D-xylopyranosyl-(1→3)]-O-β-D-glucopyranosyl-(1→4) -D-galactose (lycotetraose) is a key constituent of many biologically interesting natural products. Described herein is a convenient enzymatic preparation of lycotetraose from the readily available Solanum glycoalkaloid α-tomatine. The preparation makes use of the recombinant endo-glycosidase, tomatinase, from the plant pathogen Fusarium oxysporum f. sp. lycopersici.
- Woods, Katherine,Hamilton, Chris J.,Field, Robert A.
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- Solanum alkaloids, 139: Photolysis of N-chlorospirosolanes
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UV irradiation of N-chlorosoladulcidine (2) in trifluoroacetic acid, followed by separation and hydrolysis of the obtained 3-O-trifluoroacetates affords (23R)-23-chlorosoladulcidine (5) and 23,23-dichlorosoladulcidine (7). Similar treatment of N-chlorotomatidine (9) affords 23,23-dichloro-22-isotomatidine (12). VCH Verlagsgesellschaft mbH, 1997.
- Quyen, Le Thi,Himmelreich, Uwe,Schreiber, Klaus
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- Concise large-scale synthesis of tomatidine, a potent antibiotic natural product
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Tomatidine has recently generated a lot of interest amongst the pharmacology, medicine, and biology fields of study, especially for its newfound activity as an antibiotic agent capable of targeting multiple strains of bacteria. In the light of its low natural abundance and high cost, an efficient and scalable multi-gram synthesis of tomatidine has been developed. This synthesis uses a Suzuki–Miyaura-type coupling reaction as a key step to graft an enantiopure F-ring side chain to the steroidal scaffold of the natural product, which was accessible from low-cost and commercially available diosgenin. A Lewis acid-mediated spiroketal opening followed by an azide substitution and reduction sequence is employed to generate the spiroaminoketal motif of the natural product. Overall, this synthesis produced 5.2 g in a single pass in 15 total steps and 15.2% yield using a methodology that is atom economical, scalable, and requires no flash chromatography purifications.
- Boudreault, Pierre-Luc,Normandin, Chad
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- Gram-Scale Synthesis of Tomatidine, a Steroid Alkaloid with Antibiotic Properties Against Persistent Forms of Staphylococcus aureus
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We herein describe the first diastereoselective synthesis of the Solanum alkaloid tomatidine 1. The synthesis has been accomplished in 11 steps and 24.9 % overall yield (longest linear sequence). This methodology, which involves a convergent synthon insertion followed by a sequence of ring opening/nitrogen substitution/ring closing, allowed the generation of 1 on > 2 g scale. The synthetic challenge with the diastereoselective generation of the unusual spiroaminoketal moiety was solved through a combined azide reduction/addition sequence. The first diastereoselective synthesis of the phytosteroid yamogenin is also reported. Tomatidine has shown promising antibiotic properties against persistent forms of Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA). In particular, it possesses the unique ability to kill persistent forms of S. aureus and MRSA while simultaneously potentiating the antibiotic efficacy of aminoglycoside antibiotics against wild type strains of the bacteria.
- Normandin, Chad,Malouin, Fran?ois,Marsault, Eric
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p. 2693 - 2698
(2020/05/04)
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- PRODUCTION METHOD OF TOMATIDINE
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PROBLEM TO BE SOLVED: To provide a production method of tomatidine which can be used as a health food product or a medicament by converting tomatine which is one kind of gluco alkaloids included in a tomato plant body into tomatidine which has no toxicity and for which a prevention effect of age-related muscle atrophy can be expected. SOLUTION: The invention is configured so that, a leaf, a stem, a lateral bud, a petal, an immature fruit, and a root are cut, or are pulverized after drying, then water is added to the pulverized object per weight, the amount of the water being 3-15 times of the pulverized object, then an acid solution is added for adjusting pH of the mixture of the pulverized object and water to 2-5, then, the mixture is agitated and mixed for 30-120 minutes under temperature of room temperature to 80°C, for extracting tomatine including dehydro tomatine of glycosylated alkaloid, then an alkali solution is added to the extract then the mixture of the alkali solution and the extract is adjusted so that pH becomes 8 or higher and less than 10 in room temperature for deposition of tomatine, then after collecting deposited tomatine, then the deposited tomatine is dissolved in an acid solution of 0.5-2N, then the mixture of the acid solution and the deposited tomatine is heated for 1-4 hours at 60°C-80°C for converting the tomatine into tomatidine, then using the alkali solution again for adjusting the pH of the mixture to become 8 or more and less than 10 for deposition of the tomatidine, then the deposited tomatidine is collected, then the deposited tomatidine is dissolved in an ethanol solution whose density is 70% or more for deposition of mixed impurities for removing the impurities, then the ethanol is evaporated. SELECTED DRAWING: None COPYRIGHT: (C)2019,JPOandINPIT
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Paragraph 0041-0043
(2019/01/05)
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- Metabolism of the tomato saponin α-tomatine by Gibberella pulicaris
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The ascomycete Gibberella pulicaris is able to metabolize the saponin α-tomatine within 2 h by first removing the complete lycotetraose moiety leading to the aglycone tomatidine. This product is further converted into 7α-hydroxy-tomatidine and the corresponding Δ5-dehydro product 7α- hydroxy-tomatidenol. Structural evidence for the hydroxylated main metabolite as well as the unsaturated minor product is based on MS and NMR measurements. The latter include the application of modern soft pulse 1H NMR techniques allowing the definitive localization of the position of hydroxylation even for the few milligram quantities that could be obtained.
- Weltring, Klaus-Michael,Wessels, Judith,Pauli, Guido F.
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p. 1321 - 1328
(2007/10/03)
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- ACTIVE MANGANASE DIOXIDE: A REAGENT FOR A BIOMIMETIC CYCLIZATION OF 16β-HYDROXYLATED 22.26-EPIMINOCHOLESTANES TO SPIROSOLANE ALKALOIDS
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Treatment of the 16β-hydroxylated 22.26-epiminocholestanes 1 - 4 with activated MnO2 leads in a biogenetically remarkable cyclization directly and in good yields to the corresponding spirosolane alkaloids 5 - 8.
- Adam, G.,Huong, H. Th.
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p. 1931 - 1932
(2007/10/02)
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