- Isolation and structure of a new ceramide from the basidiomycete Hygrophorus eburnesus
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A new ceramide, named hygrophamide (1), was isolated from the fruiting bodies of the basidiomycetes Hygrophorus eburnesus Fr.. The structure of the compound was elucidated as (2S, 3S, 4R, 2′R)-2-(2′-hydroxy- 9′Z-ene-tetracosanoylamino)-octadecane- 1,3,4-triol (1) by spectral and chemical methods.
- Qu, Yan,Zhang, Hong-Bin,Liu, Ji-Kai
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Read Online
- Phytoceramides and acylated phytosterol glucosides from Pterospermum acerifolium Willd. seed coat and their osteogenic activity
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Phytochemical investigation of seed coats of Pterospermum acerifolium afforded two phytoceramides (1, 2) and two acylated phytosterol glucosides (3, 4) together with five known compounds (5-9). Their structures were elucidated on the basis of extensive sp
- Dixit, Preety,Chand, Kailash,Khan, Mohd Parvez,Siddiqui, Jawed Akhtar,Tewari, Deepshikha,Ngueguim, Florence Tsofack,Chattopadhyay, Naibedya,Maurya, Rakesh
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Read Online
- Paxillamide: A novel phytosphingosine derivative from the fruiting bodies of Paxillus panuoides
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The new phytosphingosine-type ceramide 1, named paxillamide (=2,3-dihydroxy-N-[(1S,2S,3R)-2,3-dihydroxy-1-(hydroxymethyl)heptadecyl] tetracosanamide), was isolated from the CHCl3/MeOH extract of the fruiting bodies of the Basidiomycete Paxillus panuoides, and its structure was elucidated by spectroscopic and chemical methods.
- Gao, Jin-Ming,Zhang, An-Ling,Zhang, Cun-Li,Liu, Ji-Kai
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Read Online
- Convergent evolution of bacterial ceramide synthesis
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The bacterial domain produces numerous types of sphingolipids with various physiological functions. In the human microbiome, commensal and pathogenic bacteria use these lipids to modulate the host inflammatory system. Despite their growing importance, their biosynthetic pathway remains undefined since several key eukaryotic ceramide synthesis enzymes have no bacterial homolog. Here we used genomic and biochemical approaches to identify six proteins comprising the complete pathway for bacterial ceramide synthesis. Bioinformatic analyses revealed the widespread potential for bacterial ceramide synthesis leading to our discovery of a Gram-positive species that produces ceramides. Biochemical evidence demonstrated that the bacterial pathway operates in a different order from that in eukaryotes. Furthermore, phylogenetic analyses support the hypothesis that the bacterial and eukaryotic ceramide pathways evolved independently. [Figure not available: see fulltext.]
- Ashley, Ben,Campopiano, Dominic J.,Chamberlain, Joshua D.,Coleman, Aimiyah,D’Emilia, Rachel,Fu, Larina,Guan, Ziqiang,Hansen, Matthew E. B.,Klein, Eric A.,Mohan, Eric C.,Nguyen, Hung,Stankeviciute, Gabriele,Tang, Peijun
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- Development of an Amino Acid/Hydroxy Oxime Dual Catalyst System for Highly Stereoselective Direct Asymmetric Aldol Reactions in the Presence of Water
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An eco-friendly dual catalyst system for stereoselective aldol reactions in the presence of water is described. It is based on the cooperative action of acyclic amino acids and H-bond donating hydroxy oxime catalysts. The synthetic utility of this dual catalyst system was further demonstrated by applying it as the key step in the expeditious and highly stereoselective total synthesis of d-lyxo-phytosphingosine (29% overall yield). Here the amino acid/hydroxy oxime system significantly accelerated the direct aldol reactions in the presence of water as compared to organic solvents. The stereo- and chemoselectivity were also significantly increased.
- Mridha, Moniruzzaman,Ma, Guangning,Palo-Nieto, Carlos,Afewerki, Samson,Cordova, Armando
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p. 383 - 390
(2016/12/24)
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- Chemo- and Diastereoselective N-Heterocyclic Carbene-Catalyzed Cross-Benzoin Reactions Using N-Boc-α-amino Aldehydes
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N-Boc-α-amino aldehydes are shown to be excellent partners in cross-benzoin reactions with aliphatic or heteroaromatic aldehydes. The chemoselectivity of the reaction and the facial selectivity on the amino aldehyde allow cross-benzoin products to be obtained in good yields and good diastereomeric ratios. The developed method is utilized as the key step in a concise total synthesis of d-arabino-phytosphingosine.
- Haghshenas, Pouyan,Gravel, Michel
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supporting information
p. 4518 - 4521
(2016/09/28)
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- Divergent total synthesis of D-ribo-phytosphingosine and L-ribo-phytosphingosine from D-ribose
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Divergent total synthesis of D-ribo-phytosphingosine (1) and L-ribo-phytosphingosine (2) was achieved from readily available D-ribose via cross-metathesis reaction, Wittig reaction, and diastereoselective amination reaction of allylic ethers using chlorosulfonyl isocyanate (CSI) as the key steps. As results, reactions of anti-1,2-dibenzyl ethers 11 and 16 with chlorosulfonyl isocyanate afforded exclusively anti-1,2-amino alcohols 12 and 17 with diastereoselectivity of 32:1 and 31:1 in 75% and 76% yields, respectively. These results could be explained by the neighboring group effect, leading to retention of stereochemistry.
- Chun, Jong Soo,Hong, Seung Min,Jeon, Tae Hong,Park, Sook Jin,Son, Han Pyo,Jung, Jun Min,Choi, Young Jae,Kim, In Su,Jung, Young Hoon
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p. 8550 - 8556
(2016/12/09)
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- Protein and peptide-free synthetic vaccines against streptococcus pneumoniae type 3
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The present invention provides a protein- and peptide-free conjugate comprising a synthetic carbohydrate and a carrier molecule, wherein the synthetic carbohydrate is a Streptococcus pneumoniae type 3 capsular polysaccharide related carbohydrate and the carrier molecule is a glycosphingolipid. Said conjugate and pharmaceutical composition thereof are useful for immunization against diseases associated with Streptococcus pneumoniae, and more specifically against diseases associated with Streptococcus pneumoniae type 3.
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Paragraph 0099
(2015/03/31)
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- PROTEIN AND PEPTIDE-FREE SYNTHETIC VACCINES AGAINST STREPTOCOCCUS PNEUMONIAE TYPE 3
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The present invention provides a protein- and peptide-free conjugate comprising a synthetic carbohydrate and a carrier molecule, wherein the synthetic carbohydrate is a Streptococcus pneumoniae type 3 capsular polysaccharide related carbohydrate and the carrier molecule is a glycosphingolipid. Said conjugate and pharmaceutical composition thereof are useful for immunization against diseases associated with Streptococcus pneumoniae, and more specifically against diseases associated with Streptococcus pneumoniae type 3.
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Page/Page column 71; 72
(2015/04/15)
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- CARBOHYDRATE-GLYCOLIPID CONJUGATE VACCINES
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The present invention relates to the field of synthesizing and biologically evaluating of a novel class of carbohydrate-based vaccines. The new vaccines consist of a multi-modular structure which allows applying the vaccine to a whole variety of pathogenes. This method allows preparing vaccines against all pathogens expressing immunogenic carbohydrate antigens. As conjugation of antigenic carbohydrates to proteins is not required the conjugate vaccine is particularly heat stable. No refrigeration is required, a major drawback of protein-based vaccines.
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Paragraph 0235
(2015/09/28)
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- Exploring the reactivity of chiral glycidic amides for their applications in synthesis of bioactive compounds
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A new class of chiral sulfonium salts, derived from L- and D-methionine, has been designed and successfully employed in our laboratories for the diastereoselective synthesis of glycidic amides. The epoxy amides obtained were converted cleanly into 1,2-difunctionalized products through oxirane ring-opening reactions with different types of nucleophiles. The resulting ring-opened products represent valuable and useful building blocks for the synthesis of different bioactive products. Thus, the expedient synthesis of clavaminol H as well as the synthesis of key precursors for other bioactive compounds, for example, polyketide-derived natural products, have been achieved, demonstrating the synthetic efficiency and utility of this chemistry. The reactivity of chiral epoxy amides, efficiently prepared by a new asymmetric epoxidation methodology, has been explored through their reactions with various nucleophiles. The high regioselectivity and complete stereoselectivity observed for these ring-opening reactions were applied to the synthesis of bioactive compounds. Copyright
- Sarabia, Francisco,Vivar-Garcia, Carlos,Garcia-Ruiz, Cristina,Sanchez-Ruiz, Antonio,Pino-Gonzalez, Maria Soledad,Garcia-Castro, Miguel,Chammaa, Samy
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p. 3847 - 3867
(2014/06/24)
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- A stereocontrolled route to d-ribo-phytosphingosine and sphinganine from an achiral secondary homoallylic alcohol using Sharpless kinetic resolution
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A facile and efficient enantioselective route for the synthesis of d-ribo-phytosphingosine (1a) and sphinganine (1b) has been developed employing commercially available and cheap starting material trans-cinnamaldehyde 2. The synthetic strategy features the Sharpless kinetic resolution, regioselective epoxide opening and Wittig olefination as the key steps.
- Devi, Thongam Joymati,Saikia, Bishwajit,Barua, Nabin C.
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p. 3817 - 3822
(2013/06/27)
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- Isolation and characterization of the chemical constituents from Plumeria rubra
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Rubranonoside (=7-O-α-l-rhamnopyranosyl-4′-O-β-d- glucopyranosylnaringenin; (1), a new flavanone glycoside, rubranin (=(2S,3S,4R)-2-{[(2R,16E)-2-hydroxyhexaeico-16-en]amino}octadecane-1,3, 4-triol-1-O-β-d-glucopyranoside; (2), a new sphingolipid, rubradoid (plumieridine-1-O-β-d-galactopyranoside; (3), a new iridoid galactoside, rubrajaleelol (4) and rubrajaleelic acid (5), two new nor-terpenoids together with known iridoids: 1-α-plumieride (6), plumieride p-Z-coumarate (7) and plumieride-p-E-coumarate (8) have been isolated from the EtOAc-soluble fraction of the MeOH extract of Plumeria rubra. Their structures were assigned from 1H, 13C NMR spectra and 2D NMR analyses (COSY, NOESY, HMQC and HMBC experiments) in combination with HRMS experiments and comparison with literature data of related compounds. All the isolates (1-8) were tested for their antioxidant, antiurease, cytotoxic and phytotoxic activities and were found almost inactive.
- Akhtar, Nasim,Saleem, Muhammad,Riaz, Naheed,Ali, M. Shaiq,Yaqoob, Asma,Nasim, Faiz-Ul-Hassan,Jabbar, Abdul
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p. 291 - 298
(2013/08/25)
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- Total synthesis of N,O,O,O-tetraacetyl-d-ribo-phytosphingosine and its 2-epi-congener
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Total synthesis of the natural d-ribo-phytosphingosine I and its 2-epimer III in the protected form was achieved through a common strategy. The aza-Claisen rearrangement of allylic thiocyanate (Z)-V incorporated the new stereogenic centre with nitrogen and the subsequent Wittig olefination constructed a non-polar side chain. Hydrogenation, followed by removal of protecting groups, completed the syntheses of I and III.
- Martinkova, Miroslava,Pomikalova, Kvetoslava,Gonda, Jozef
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p. 84 - 91,8
(2020/08/24)
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- Total synthesis of d - Lyxo -phytosphingosine and formal synthesis of pachastrissamine via a chiral 1,3-oxazine
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Concise and efficient syntheses of d-lyxo-phytosphingosine and pachastrissamine were achieved utilizing a chiral oxazine. The key features in these strategies are the stereoselective intramolecular oxazine formation catalyzed by palladium(0), and intermolecular olefin cross-metathesis. Georg Thieme Verlag Stuttgart · New York.
- Mu, Yu,Kim, Ji-Yeon,Jin, Xiangdan,Park, Seok-Hwi,Joo, Jae-Eun,Ham, Won-Hun
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experimental part
p. 2340 - 2346
(2012/09/07)
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- Total syntheses of D -xylo- and D -arabino-phytosphingosine based on the syntheses of chiral 1,3-oxazines
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An efficient, stereocontrolled, and short synthetic method for the preparation D-xylo- and D-arabino-phytosphingsine was achieved utilizing chiral oxazines. The key features of this strategy are the stereoselective intramolecular oxazine formation catalyzed by palladium(0) and an intermolecular olefin cross-metathesis reaction.
- Mu, Yu,Jin, Tian,Kim, Gun-Woo,Kim, Jin-Seok,Kim, Sung-Soo,Tian, Yong-Shou,Oh, Chang-Young,Ham, Won-Hun
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experimental part
p. 2614 - 2620
(2012/07/13)
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- Stereoselective synthesis of N,O,O,O-tetraacetyl-D-ribo-phytosphingosine, N,O,O-triacetyl-D-erythro-sphingosine and N,O,O-triacetyl sphingonine from a common chiral intermediate derived from D-mannitol
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An efficient protocol for the stereoselective synthesis of tetraacetyl-D-ribo-hytosphingosine, triacetyl-D-erythro-sphingosine and triacetyl sphinganine has been devised from a common chiral intermediate derived from commercially available D-mannitol. The key steps involved are Sharpless epoxidation, Miyashita C(2) selective endo mode azide opening of 2,3-epoxy alcohol, and selective E-Wittig olefination. ARKAT-USA, Inc.
- Mettu, Ravinder,Thatikonda, Narendar Reddy,Olusegun, Oladoye Sunday,Vishvakarma, Ramesh,Vaidya, Jayathirtha Rao
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p. 421 - 436
(2013/11/06)
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- A flexible approach to construct three contiguous chiral centers of sphingolipids, and asymmetric synthesis of d-ribo-phytosphingosine and its derivatives
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An efficient approach to build the three contiguous stereogenic centers of sphingosine unit starting from cheap glutamic acid is described. The key step of this approach is the SmI2-mediated cross-coupling of chiral N-tert-butanesulfinyl imine 11 with sterically hindered aliphatic aldehyde 9 or 21 to construct hydroxymethyl β-amino alcohol 10 or 22 in high diastereoselectivity (>99%, de). The utility of this flexible method has been demonstrated in the synthesis of d-ribo-phytosphingosine 1, its two derivatives 18 and 29. Moreover, a practicable synthetic route for synthesis of various sphingolipids, ceramides, α-galactosylceramides and their derivatives is also described.
- Chao, Cholmen Xarnod Lu-Men,Huang, Wei,Ren, Rong-Guo,Liu, Ru-Cheng,Wei, Bang-Guo
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p. 6688 - 6695
(2012/09/05)
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- Cytotoxic ceramides and glycerides from the roots of Livistona chinensis
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A 70% ethanol extract of the roots of Livistona chinensis has been investigated, led to the isolation of 13 compounds, including a new ceramide, (2S,3S,4R,9Z)-2-[(2R)-2-hydroxytricosanoylamino]-9-octadecene-1,3,4-triol (2), a new glycosyl ceramide, 1-O-β-d-glucopyranosyl-(2S,3S,4R,9Z)-2-[(2R)-2- hydroxydocosanoylamino]-9-octadecene-1,3,4-triol (3), three new monoacylglycerols, 1-(34-hydroxytetratriacontanoyl)-sn-glycerol (9), 1-[nonadeca-(9Z,12Z)-dienoyl]-sn-glycerol (10), and 1-[12-hydroxypentatriaconta- (13E,15Z)-dienoyl]-sn-glycerol (11), a new diacylglycerol, 1-(heptadeca-6Z,9Z- dienoyl)-3-(octadeca-6Z,9Z,12Z-trienoyl)-sn-glycerol (12), as well as a new diacylglycerol aminoglycoside, 1-octadecanoyl-2-nonadecanoyl-3-O-(6-amino-6- deoxy)-β-d-glucopyranosyl-sn-glycerol (13). The structures of new compounds were elucidated, based on spectroscopic, zymologic and chemical methods. Among the compounds tested, compounds 3, 4 and 13 showed significantly antiproliferative effects against the human tumor cell lines (K562, HL-60, HepG2, and CNE-1) with the IC50 of 10-65 μM. To our knowledge, this is first report of the occurrence of ceramides and acylglycerols in the genus Livistona.
- Zeng, Xiaobin,Xiang, Limin,Li, Chen-Yang,Wang, Yihai,Qiu, Guofu,Zhang, Zhen-Xue,He, Xiangjiu
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experimental part
p. 609 - 616
(2012/06/04)
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- ENZYMATIC SYNTHESIS OF SPHINGOLIPIDS
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The invention relates to the enzymatic synthesis of sphingolipids and compositions that contain sphingolipids from lysosphingolipids and carbonic esters, and to cosmetic, dermatological or pharmaceutical formulations containing said sphingolipids or compositions.
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(2011/04/19)
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- An efficient synthesis of D-ribo-C18-phytosphingosine and L-arabino-C18-phytosphingosine from D-fructose
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D-ribo-C18-phytosphingosine and L-arabino-C18- phytosphingosine were synthesised starting from commercially inexpensive D-fructose. Metal-mediated fragmentation and stereoselective reduction were used as key steps to provide the hydrophilic portion of D-ribo and L-arabino phytosphingosines. Grubbs' cross-metathesis and hydrogenation allowed the incorporation of hydrophobic tail.
- Perali, Ramu Sridhar,Mandava, Suresh,Chalapala, Sudharani
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p. 9283 - 9290
(2011/12/03)
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- EFFICIENT METHODS FOR Z- OR CIS-SELECTIVE CROSS-METATHESIS
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The present invention generally relates to methods for performing metathesis reactions, including cross-metathesis reactions. Methods described herein exhibit enhanced activity and stereoselectivity, relative to known methods, and are useful in the synthe
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Page/Page column 84; 5/6
(2011/09/14)
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- Regioselective inversion of the hydroxyl group in d-ribo-phytosphingosine via a cyclic sulfate and bis-sulfonate intermediate
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The selective synthesis of d-xylo-and d-lyxo-phytosphingosines from commercially available d-ribo-phytosphingosine is described. Thermolysis of the N-carbonyl protected cyclic sulfate led to an inversion of configuration of the proximal hydroxyl group to
- Lee, Yun Mi,Baek, Dong Jae,Lee, Seokwoo,Kim, Deukjoon,Kim, Sanghee
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experimental part
p. 408 - 416
(2011/03/20)
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- A common and stereoselective strategy for the synthesis of N,O,O,O-tetra-acetyl d-ribo-(2S,3S,4R)-phytosphingosine and 2-epi-jaspine B
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A common and stereoselective strategy for the synthesis of N,O,O,O-tetra-acetyl d-ribo-(2S,3S,4R)-phytosphingosine and 2-epi-jaspine B was achieved by using Grignard addition on N-benzyl sugar lactamine and Wittig olefination as key steps.
- Srinivas Rao,Venkateswara Rao
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p. 4861 - 4864
(2011/10/07)
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- Syntheses and biological activities of KRN7000 analogues having aromatic residues in the acyl and backbone chains with varying stereochemistry
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KRN7000 is an important ligand identified for CD1d protein of APC, and KRN7000/CD1d complex can stimulate NKT cells to release a broad range of bioactive cytokines. In an effort to understand the structure-activity relationships, we have carried out synth
- Park, Jeong-Ju,Lee, Ji Hyung,Seo, Kyung-Chang,Bricard, Gabriel,Venkataswamy, Manjunatha M.,Porcelli, Steven A.,Chung, Sung-Kee
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supporting information; scheme or table
p. 814 - 818
(2010/06/16)
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- Asymmetric synthesis of d - Ribo -phytosphingosine from 1-tetradecyne and (4-Methoxyphenoxy)acetaldehyde
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(Figure presented) An asymmetric synthesis of d-ribo-phytosphingosine (1) was achieved by utilizing the ProPhenol (12)-catalyzed alkynylation of unsaturated aldehyde 8 to afford allylic propargylic alcohol (S)-6 followed by asymmetric epoxidation and opening of propargylic epoxy alcohol anti-5 with NaN3/NH4Cl. Deprotection and reduction of the resulting acyclic azide 3 then gave 1. Alkyne-azide 3 was subjected to an intramolecular click reaction, generating a bicyclic triazole, which was found to have unexpected vicinal coupling constants. Application of the advanced Mosher method verified the configurations of the three contiguous stereogenic centers of 1. An alkynyl azide analogue of 1, which may be useful as a glycosyl acceptor in the synthesis of α-galactosylceramide derivatives, was also readily prepared by this route.
- Liu, Zheng,Byun, Hoe-Sup,Bittman, Robert
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supporting information; experimental part
p. 4356 - 4364
(2010/10/02)
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- An efficient and general enantioselective synthesis of sphingosine, phythosphingosine, and 4-substituted derivatives
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A general and efficient protocol for the enantioselective synthesis of sphingosine, phythosphingosine, and 4-substituted derivatives was established. These compounds were obtained from a common intermediate prepared from butadiene monoepoxide by a synthet
- Llaveria, Josep,Diaz, Yolanda,Matheu, M. Isabel,Castillon, Sergio
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supporting information; experimental part
p. 205 - 208
(2009/06/20)
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- Efficient and selective synthesis of D-arabino-, D-lyxo-, and D-xylo-phytosphingosine from D-ribo-phytosphingosine
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(Chemical Equation Presented) A new high-yield approach to the regio- and stereoselective synthesis of D-arabino-, D-lyxo-, and D-xylo-phytosphingosines from inexpensive D-ribo-phytosphingosine is described. The synthetic methodologies mainly rely on the
- Kim, Sanghee,Lee, Nakyong,Lee, Sukjin,Lee, Taeho,Yun, Mi Lee
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p. 1379 - 1385
(2008/04/12)
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- Jaspine B (pachastrissamine) and 2-epi-jaspine B: synthesis and structural assignment
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Jaspine B (pachastrissamine), which was isolated in 2002, is a naturally occurring anhydrophytosphingosine which displays potent biological activity, and as such has attracted much attention from synthetic chemists in recent years, with 14 syntheses reported to date. This review delineates the isolation of jaspine B, and laboratory total syntheses of jaspine B, 2-epi-jaspine B and analogues, which serves to confirm their structure and stereochemistry.
- Abraham, Elin,Davies, Stephen G.,Roberts, Paul M.,Russell, Angela J.,Thomson, James E.
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p. 1027 - 1047
(2008/09/20)
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- Asymmetric synthesis of N,O,O,O-tetra-acetyl d-lyxo-phytosphingosine, jaspine B (pachastrissamine), 2-epi-jaspine B, and deoxoprosophylline via lithium amide conjugate addition
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The highly diastereoselective anti-aminohydroxylation of (E)-γ-tri-iso-propylsilyloxy-α,β-unsaturated esters, via conjugate addition of lithium (S)-N-benzyl-N-(α-methylbenzyl)amide and subsequent in situ enolate oxidation with (+)-(camphorsulfonyl)oxaziri
- Abraham, Elin,Brock, E. Anne,Candela-Lena, José I.,Davies, Stephen G.,Georgiou, Matthew,Nicholson, Rebecca L.,Perkins, James H.,Roberts, Paul M.,Russell, Angela J.,Sánchez-Fernández, Elena M.,Scott, Philip M.,Smith, Andrew D.,Thomson, James E.
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supporting information; experimental part
p. 1665 - 1673
(2008/10/09)
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- Improved synthesis of phytosphingosine and dihydrosphingosine from 3,4,6-Tri-O-benzyl-D-galactal
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An efficient and facile synthesis of phytosphingosine and dihydrosphingosine derivatives is described with less steps and in improved overall yield (66-72%) starting from commercially available tri-O-benzyl-D- galactal. The key steps include Wittig reaction, Mitsunobu transformation, reduction, and deprotection.
- Niu, Youhong,Cao, Xiaoping,Ye, Xin-Shan
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experimental part
p. 746 - 752
(2009/02/07)
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- Synthesis and preliminary antifungal evaluation of a library of phytosphingolipid analogues
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A library of 64 phytosphingolipid analogues resulting from the systematic variation of the C1, C3, C4, and the N-acyl moiety of phytosphingosine (PHS) has been prepared from common scaffolds derived from the chiral pool and Sharpless asymmetric dihydroxylation reactions. Library members have been evaluated as growth inhibitors of the yeast Saccaromyces cerevisiae. In addition, 1-amino-N-pivaloyl PHS analogues were also tested as IPC synthase inhibitors, in comparison with the natural product khafrefungin. The Royal Society of Chemistry 2007.
- Mormeneo, David,Casas, Josefina,Llebaria, Amadeu,Delgado, Antonio
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p. 3769 - 3777
(2008/10/09)
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- Concise syntheses of immunostimulating glycolipids, α-galactosyl ceramides
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α-Galactosylceramides (α-GalCers) are well known as immunostimulating agents having therapeutic potential. To facilitate the synthesis of α-GalCers and their derivatives, a novel and convergent strategy was designed, which is expected to be versatile for the preparation of a variety of analogues in a diversity-oriented fashion. As an initial demonstration of our strategy, KRN7000 and OCH were synthesized in eight steps from a common intermediate, which is easily obtainable in a multi-gram scale.
- Tsujimoto, Takashi,Ito, Yukishige
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p. 5513 - 5516
(2008/02/10)
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- Dihydroxylation of 2-vinylaziridine: Efficient synthesis of D-ribo-phytosphingosine
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An efficient and highly stereoselective synthesis of D-ribo-(2S,3S,4R)- phytosphingosine was accomplished in 62% overall yield starting from commercially available (2S)-hydroxymethylaziridine via osmium-catalyzed asymmetric dihydroxylation as a key step. The Royal Society of Chemistry.
- Yoon, Hyo Jae,Kim, Yong-Woo,Lee, Baeck Kyoung,Lee, Won Koo,Kim, Yongeun,Ha, Hyun-Joon
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- An improved synthesis of ceramide for constructing α-galactosyl ceramide analogs
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In spite of numerous synthetic routes to ceramide analogs, relatively few reports of the direct coupling of the unprotected phytosphingosine with the activated palmitic acid via amide bond formation are available. After purification by HPLC, the chromatogram indicated some impurities had not been removed during previous column chromatography. With the pure ceramides in hand, derivatization with the amino group for constructing libraries could be realized.
- Yeh, Chien-Hung,Pan, Si-Der,Chen, Shao-Wei,Fu, Zhi-Wei,Chiang, Li-Wu,Yu, Chung-Shan
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p. 1375 - 1378
(2008/02/13)
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- A general, efficient and stereospecific route to sphingosine, sphinganines, phytosphingosines and their analogs
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Sphingosine, sphinganines and phytosphingosines and their analogs were synthesized by an aldol condensation between an iminoglycinate bearing a (+)-(1R,2R,5R)-2-hydroxy-3-pinanone group as chiral auxiliary and an appropriate aldehyde. All condensations proceeded with excellent enantioselectivity to generate the (2S,3R)-d-erythro structures in good yields. The Royal Society of Chemistry 2006.
- Cai, Ye,Ling, Chang-Chun,Bundle, David R.
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p. 1140 - 1146
(2008/02/03)
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- An efficient high-yield synthesis of D-ribo-phytosphingosine
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[4R-[4α(S*),5α]]-2,2-Dimethyl-4-(2-oxo-5-vinyl[1,3] dioxolan-4-yl)oxazolidine-3-carboxylic acid tert-butyl ester 5a, obtained in excellent yield and diastereoselectivity by the α-hydroxyallylation of the Garner aldehyde (4), is exploited in a novel high-yield synthesis of D-ribo-phytosphingosine (8), using microwave-enhanced cross metathesis as the key step in the chain elongation.
- Lombardo, Marco,Capdevila, Montse Guiteras,Pasi, Filippo,Trombini, Claudio
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p. 3303 - 3305
(2007/10/03)
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- Highly efficient stereoselective synthesis of d-erythro-sphingosine and d-lyxo-phytosphingosine
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Starting from a single suitable functionalised epoxide, a highly efficient stereoselective synthesis of d-erythro-sphingosine and d-lyxo-phytosphingosine is described. The approach allows the formal preparation of all stereoisomers of these sphingoid stru
- Righi, Giuliana,Ciambrone, Simona,D'Achille, Claudia,Leonelli, Andrea,Bonini, Carlo
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p. 11821 - 11826
(2007/10/03)
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- A direct organocatalytic entry to sphingoids: Asymmetric synthesis of D-arabino- and L-ribo-phytosphingosine
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The organocatalytic asymmetric synthesis of d-arabino- and l-ribo-phytosphingosine is described employing a diastereo- and enantioselective (S)-proline-catalyzed aldol reaction of 2,2-dimethyl-1,3-dioxan-5-one and pentadecanal as the key step. The Royal S
- Enders, Dieter,Palecek, Jiri,Grondal, Christoph
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p. 655 - 657
(2008/02/10)
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- An efficient synthesis of D-ribo- and L-lyxo-phytosphingosine from D-tartaric acid
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The preparations of D-ribo- and L-lyxo-phytosphingosines (1, 2) are described. Chelation-controlled addition of tetradecylmagnesium bromide to pentylidene-protected D-threitol aldehyde 6 afforded the key intermediate tetrol 7, providing the desired L-lyxo stereochemistry of phytosphingosine. Inversion at C4 of intermediate 7 provided the D-ribo stereochemistry.
- Lu, Xuequan,Bittman, Robert
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p. 3165 - 3168
(2007/10/03)
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- Efficient enantioselective total synthesis of arabino-phytosphingosine
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Enantioselective total synthesis of arabino-phytosphingosine has been achieved in 8 steps employing Claisen rearrangement and Fleming-Tamao oxidation as key steps. Installation of all chiral centers present in arabino- phytosphingosine was achieved throug
- Jung, Doo Young,Kang, Sol,Chang, Suk Bok,Kim, Yong Hae
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p. 2183 - 2186
(2007/10/03)
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- Synthesis of L-lyxo-phytosphingosine and its 1-phosphonate analogue using a threitol acetal synthon
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The first synthesis of an isosteric phosphonate analogue of the aminotriol lipid phytosphingosine (3), together with an improved synthesis of (2S,3S,4S)-phytosphingosine (2), are described. A key intermediate is 3-pentylidene acetal 9, which was prepared in two steps from dimethyl 2,3-0-benzylidene-D-tartrate (7).
- Lu, Xuequan,Byun, Hoe-Sup,Bittman, Robert
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p. 5433 - 5438
(2007/10/03)
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- A concise route to phytosphingosine from lyxose
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Phytosphingosine was synthesized from the commercially available D-2,3-O-isopropylidene-D-lyxofuranose in 28% overall yield by a six-step procedure. This procedure is expedient and flexible for introduction of other lipid moieties on the phytosphingosine structure to make a variety of derivatives that can support the further exploration of their related biological functions.
- Lin, Chun-Cheng,Fan, Gang-Ting,Fang, Jim-Min
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p. 5281 - 5283
(2007/10/03)
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- A facile synthesis of phytosphingosine from diisopropylidene-D-mannofuranose
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In the present study, an efficient method with a high overall yield for preparing phytosphingosine and an analogue was developed. Starting with commercially available 2,3;5,6-di-O-isopropylidene-D-mannofuranose, a variety of lipid moieties were incorporated to obtain phytosphingosine and an analogue. Through an eight-step manipulation, phytosphingosine was obtained with an overall yield of 57%.
- Chiu, Hsin-Yi,Tzou, Der-Lii M.,Patkar, Laxmikant Narhari,Lin, Chun-Cheng
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p. 5788 - 5791
(2007/10/03)
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- Enantioselective synthesis of D-ribo-(2S,3S,4R)-C18-phytosphingosine using double stereodifferentiation
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An enantioselective synthesis of D-ribo-C18-phytosphingosine as its tetraacetate derivative 10, starting from D-mannitol and employing the Sharpless asymmetric dihydroxylation reaction on allylic alcohol 6 as the key step, is described.
- Naidu, S. Vasudeva,Kumar, Pradeep
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p. 1035 - 1037
(2007/10/03)
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- Synthesis of D-ribo-C18-phytosphingosine from D-glucosamine via the D-allosamine derivatives as key intermediates
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A straightforward synthesis of D-ribo-C18-phytosphingosine from D-glucosamine hydrochloride in ten steps in 18.4% overall yield via the D-allosamine derivatives as key intermediates is described here.
- Luo, Shun-Yuan,Thopate, Shankar R.,Hsu, Ching-Yun,Hung, Shang-Cheng
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p. 4889 - 4892
(2007/10/03)
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- Stereoselective synthesis of D-erythro-sphingosine and L-lyxo-phytosphingosine
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An alternative synthetic route to D-erythro-sphingosine and L-lyxo-phytosphingosine was developed, utilizing chiral β-lactam 3 obtained from D-(-)-tartaric acid as a starting material.
- Nakamura, Tsuyoshi,Shiozaki, Masao
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p. 9087 - 9092
(2007/10/03)
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- A Stereocontrolled, Efficient Synthetic Route to Bioactive Sphingolipids: Synthesis of Phytosphingosine and Phytoceramides from Unsaturated Ester Precursors via Cyclic Sulfate Intermediates
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An efficient and highly enantioselective method for the preparation of D-ribo- and L-lyxo-phytosphingosines (1a,b, respectively) and phytoceramides (2a,b) has been developed. The key steps in the syntheses are as follows: (i) osmium-catalyzed asymmetric dihydroxylation of 4-O-protected (E)-α,β-unsaturated ester 5 (generated by dihydroxylation of 1-hexadecene, followed by oxidation to the aldehyde and Horner-Wadsworth-Emmons olefination), (ii) conversion to cyclic sulfate intermediate 7, and (iii) regioselective α-azidation of 7. Reduction of 4-O-protected 2-azido ester 8 via α-azidolactone 9 afforded phytosphingosine 1a. Staudinger reduction of the azido group of 8, followed by in situ N-acylation in aqueous media and reduction of the ester functionality with NaBH4/LiBr, provided phytoceramide 2a. By using a similar approach, phytosphingosine 1b was synthesized. D-erythro-4,5-Dihydrosphingosine 1c and D-erythro-4,5-dihydroceramide 2c were synthesized in high yield from 1-hexadecanol via cyclic sulfate intermediate 15. The desired configurations at C-2, C-3, and C-4 of the sphingoid chain can be accessed readily by the route described here.
- He, Linli,Byun, Hoe-Sup,Bittman, Robert
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p. 7618 - 7626
(2007/10/03)
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- Stereocontrolled synthesis of novel phytosphingosine-type glucosaminocerebrosides
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D-ribo-Phytosphingosine 1 was conveniently synthesized from N-benzoyl- D-glucosamine 3 by an improved route in which regioselective O- methanesulfonation and diastereoselective Grignard addition are involved as key steps. Using a synthetic intermediate of 1, novel D-ribo- phytosphingosine-type glycolipids 2a and 2b, unnatural homologues of antifungal cerebrosides Halicylindrosides, were efficiently synthesized in a stereocontrolled manner.
- Murakami, Teiichi,Taguchi, Kazuhiro
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p. 989 - 1004
(2007/10/03)
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