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Synthesis of side chain

The Michael addidon of nitto compounds is a useful method for the preparadon of various naniral products The Michael kldidon of nittoalkanes to dehydroalanines gives ynitto-ct-amino acids, which provides a convenient synthesis of side-chain modified ct-amino acids fEq 4 114 " Transformadons of Y-nitto-ct-amino acid derivadves into ct-amino adds occur by... [Pg.106]

A Aletras, K Barlos, D Gatos, S Koutsogianni, P Mamos. Preparation of the very acid-sensitive Fmoc-Lys(Mtt)-OH. Application in the synthesis of side-chain to side-chain cyclic peptides and oligolysine cores suitable for solid-phase assembly of MAPs and TASPs. Ini J Pept Prot Res 45, 488, 1995. [Pg.162]

Transformation of a phosphonio-substituted phospholide derivative under conservation of the r-electron system has been demonstrated in a number of cases which include substitution of a ring-hydrogen atom, replacement of a PRs -moiety by a hydride, or reductive de-arylation of a PhsP " - to a phosphinyl substituent PPh2. Subsequent re-quaternisation of the latter allows the formal substitution of a PhsP " - by a modified Ph2(R)P -moiety in a two-step reaction. The application of this scheme is not only perfectly suitable for the synthesis of bis-phosphonio-benzophospholides with different phosphonio-moieties but, since the last reaction stage tolerates a variety of functional groups in the electrophile, offers as well a convenient pathway for the synthesis of side-chain functionalised phosphonio-phospholide derivatives from more simple substituted precursors. [Pg.183]

Synthesis of Side-Chain-to-Side-Chain and Head-to-Side-Chain Cyclic Peptides... [Pg.491]

Scheme 8. Synthesis of side-chain 35 as the t-butyl ester. Scheme 8. Synthesis of side-chain 35 as the t-butyl ester.
Synthesis of Side-Chain Conformationally Restricted a-Amino Acids... [Pg.5]

Synthesis of Side-Chain-Substituted Oxazolidine-4-carboxylic Add Peptides... [Pg.73]

The disadvantage of this method is that saponification of the resulting ester group can result in racemization. A method for the synthesis of TV-methyl amino acids without esterification has been presented by Benoiton and co-workers,[78 95] which uses sodium hydride as the base and iodomethane in THF at room temperature. This method is also applicable to the synthesis of side-chain-functionalized amino acid derivatives when the side chain is protected by a terf-butyl-type group. [Pg.224]

Scheme 2 Synthesis of Side-Chain-Protected Peptides Employing the Oxime Resin,2l... Scheme 2 Synthesis of Side-Chain-Protected Peptides Employing the Oxime Resin,2l...
Enantiomerically pure a-amino aldehydes containing nonpolar side chains such as Boc-Ala-H, Boc-Leu-H, and Boc-Phe-H are synthesized by lithium aluminum hydride reduction of the corresponding Weinreb amides, Boc-Ala-N(Me)OMe, Boc-Leu-N(Me)OMe, and Boc-Phe-N(Me)OMe, respectively (Table 4). The lithium aluminum hydride does not affect the Boc group due to the low temperature and short 15-minute reaction time. Successful synthesis of side-chain Bzl-protected Boc-Thr(Bzl)-H gives a 95% yield of crude product, however, reduction of N-protected aspartyl and glutamyl aldehydes from their corresponding A-methoxy-A-methylamides leads to overreduction and unreacted hydroxamateJ1920 ... [Pg.205]

Cyclopentadienyl compounds of lithium, sodium, potassium, magnesium and thallium are most commonly used. The synthesis of these cyclopentadienyl-transfer agents is described in more detail in Section II.B.2. Organosilicon halides and alkoxides are the most convenient substrates. The synthesis of side-chain functionalized cyclopentadienyl silanes is described in equation 541,42 as a typical example of this strategy. [Pg.2139]

Our initial work involved the synthesis of side chains which have the molecular characteristics required for a nonlinear optical response. Compounds 1-3 were prepared by the use of Horner-Emmons-Wadsworth Wittig methodology (22). Compound 4 was commercially available (Aldrich) as the dye, Disperse Red 1. As outlined in Scheme I, in the first step in the synthesis of 1-3,... [Pg.262]

Scheme 3. Synthesis of side-chain modified compounds 94 and 95. Scheme 3. Synthesis of side-chain modified compounds 94 and 95.
Easton, C. J. Roselt, P. D. Tiekink, E. R. T. Synthesis of side-chain functionalized amino add derivatives through reaction of alkyl nitro-nates with a-bromoglydne derivatives. Tetrahedron 1995, 51, 7809-7822. [Pg.224]

Crombie, L., Edgar, A.J.B., Harper, S.H., Lowe, M.W., and Thompson, D. 1950. The synthesis of the pyrethrins. V. Synthesis of side-chain isomers and analogs of cinerone, cine-rolone, and cinerin-I. Journal of Chemical Society, 3552-63. [Pg.76]

T. Takata, H. Kawasaki, N. Kihara, Y. Furusho, Synthesis of Side-Chain Polyrotaxane by Radical Polymerizations of Pseudorotaxane Monomers Consisting of Crown Ether Wheel and Acrylate Axle Bearing Bulky End-Cap and Ammonium Group , Macromolecules, 34, 5449 (2001)... [Pg.73]

Synthesis of Side-chain Carboxy Acids.—The side-chain carhoxy acids being really aryl substituted aliphatic acids are synthesized by methods characteristic of such acids. [Pg.678]

By Grignard Reaction.—Exactly analogous to the Grignard synthesis of ring carboxy acids is the synthesis of side-chain carboxy acids by the introduction of carbon dioxide into the Grignard reagent. [Pg.680]


See other pages where Synthesis of side chain is mentioned: [Pg.467]    [Pg.121]    [Pg.121]    [Pg.898]   
See also in sourсe #XX -- [ Pg.426 ]




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Chain synthesis

Synthesis side chains

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