- Synthesis of new triazamacrocycles N-functionalised with α-(S)- hydroxycarboxylic acid pendant-arms
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The synthesis of two new macrocyclic ligands, N,N',N''-tris[2(S)- hydroxybutyric acid]-1,4,7-triazacyclononane and N,N',N''-tris[2(S)- hydroxybutyric acid]-1,5,9-triazacyclododecane is reported. Each macrocycle bears three L-lactate-like pendant arms. Starting from L-malic acid, the absolute configuration of the α-(S)-hydroxy acid was kept along the synthesis leading to pure (S,S,S) enantiomers.
- Delagrange, Samuel,Nepveu, Francoise
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- STRUCTURE AND SYNTHESIS OF AVENIC ACID B, A NEW AMINO ACID POSSESSING AN IRON CHELATING ACTIVITY
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A new amino acid derivative possessing an iron chelating activity was isolated from an ethanol extract from the roots of Avena sativa.The structure of this compound, avenic acid B, has been determined as 2(S),3'(S)-N-(3-hydroxy-3-carboxypropyl)-homoserine (1) on the basis of nmr analysis and by chemical synthesis.
- Fushiya, Shinji,Sato, Yoshikazu,Nozoe, Shigeo
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- Synthesis of (S)-vasicol and (S)-3-hydroxy-2-pyrrolidinone
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Starting from (S)-malic acid, a flexible approach to (S)-3-hydroxy-2-pyrrolidinone and (S)-1-alkyl-3-hydroxy-2-pyrrolidinones was reported. Using this method, the first total syntheses of (-)-vasicol as well as deaminovasicol were accomplished, which allowed the revision and clarification the confusion about the structure of naturally occurring (-)-vasicol.
- Huang, Pei-Qiang,Zheng, Xiao,Wei, Hua
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p. 1833 - 1841
(2007/10/03)
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- Optically active substance and liquid crystal composition comprising same
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Disclosed is an optically active substance represented by the formula: STR1 wherein m is an integer of 1 to 14, Y is STR2 R is --Cn H2n+1, --OCn H2n+1, --OCOCn H2n+1 or --COOCn H2n+1 (in which n is an integer of 1 to 18), each of the asterisked carbon atoms is an asymmetric carbon atom, X a single bond, --CO2 --, or --OCO--, and A1 and A2 is hydrogen, fluorine, chlorine, bromine, cyano or methoxy.
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- Optically active compound having XI-valerolactone ring and liquid crystal composition comprising same
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An optically active compound having a δ-valerolactone ring which is a ferroelectric liquid crystal and is represented by the following general formula (I): STR1 wherein m is an integer of from 1 to 8, Z is a group represented by the following formula: STR2 in which each of l and k is a number of 1 or 2 and l and k satisfy the requirement of 2≤(l+k)≤3, X stands for a direct bond, STR3 Y stands for STR4 and A1 and A2 independently stand for --H, --F or --Cl, STR5 R stands for STR6 in which n is an integer of from 1 to 18, and * indicates the asymmetric carbon atom.
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- Optically active substance and liquid crystal composition
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An optically active substance having a δ-valero-lactone ring is described which is represented by the formula (1): wherein X is -O-, -OCH2- or -SCH2-, R1 is C1 - 18 alkyl, n is an integer of from 1 to 14, m is 1 or 0, Y is
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- Optical active compound and liquid crystal composition
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Disclosed is an optically active compound repre-sented by the formula: (k = 1 - 14, X1 is direct bond or -O-, *C is an asymmetric carbon), R is linear alkyl, optically active monohalogenoalkyl or op-tically active alkyl with CH3 branch, X is direct bond, -O-, -CO2- or -OCO-, Y is direct bond, -OCO-, -CO2-, -CH2O- or -OCH2-, A1 and (B is H, halo or cyano), m = 0 or 1, n = 1 - 14, Z1 is -CO2- or -CH2O-, and Z2 is -CO2-, -CH2O- or -O-, with the proviso that when m = 0 in formula (2), A3 is and when Y is direct bond and Z2 is -O- in formula (2), combination of A3 and A4 is neither combination of This compound is used as a ferroelectric liquid crystal or an additive to be incorporated with a ferroelectric liquid crystal or a non-ferroelectric liquid crystal of SmC phase.
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- Optisch aktive Lycopin-epoxide und Lycopin-glycole: Synthesen und chiroptische Eigenschaften
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We present extensive spectral and chiroptical data on the pure and crystalline lycopene diepoxides 1-3 and glycols 4-9.A first synthetic approach to 1-9 with (+)-malic acid as starting material afforded 30 as a complex mixture of isomers (Scheme 1).Pure stereoisomers 1-9 were obtained using the enantiomerically pure epoxygeraniol 31 as starting material (Scheme 2).Differentiation of the (5Z)- from the (all-E)-isomers by 1H-NMR and UV/VIS alone is very difficult.
- Meier, Heidi,Uebelhart, Peter,Eugster, Conrad Hans
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p. 106 - 123
(2007/10/02)
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- SYNTHESIS OF THE OPTICALLY ACTIVE FORMS OF 4,10-DIHYDROXY-1,7-DIOXASPIROUNDECANE AND THEIR CONVERSION TO THE ENANTIOMERS OF 1,7-DIOXASPIROUNDECANE, THE OLIVE FLY PHEROMONE
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Both the enantiomers of 1,7-dioxaspiroundecane, the major component of the pheromone of the olive fly (Dacus oleae), were synthesized from (S)-malic acid.
- Mori, Kenji,Uematsu, Tamon,Yanagi, Kazunori,Minobe, Masao
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p. 2751 - 2758
(2007/10/02)
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- SYNTHESIS OF THE ENANTIOMERS OF 1,7-DIOXASPIROUNDECANE AND 4-HYDROXY 1,7-DIOXASPIROUNDECANE, THE COMPONENTS OF THE OLIVE FLY PHEROMONE
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The enantiomers of the olive fly pheromone (1 and 4) were synthesized from (S)-malic acid in amounts sufficient for the biological test.
- Mori, Kenji,Uematsu, Tamon,Watanabe, Hidenori,Yanagi, Kazunori,Minobe, Masao
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p. 3875 - 3878
(2007/10/02)
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