9-Fluorenylmethoxycarbonyl

This is a very important and well tested method for the quantitative determination of loading of Fmoc protected compounds particularly that of Fmoc (fluorenylmethoxycarbonyl) amino acids on solid support. Fmoc groups can... 

For a review of the use of Fmoc protection in peptide synthesis, see E. Atherton and R. C. Sheppard, The Fluorenylmethoxycarbonyl Amino Protecting Group, in The... 

Cyclization of 1 -(9-fluorenylmethoxycarbonyl)-2-[(A-methoxycarbonyl-methyl)aminocarbonyl)piperidine and 2-(9-fluorenylmethoxycarbonyl) -3-[(A-methoxycarbonylmethyl)aminocarbonyl]-1,2,3,4-tetrahydroisoquino-lines on the action of piperidine in THF yielded 2-(l,4-dioxoperhydropyr-ido[ 1,2-fl]pyrazin-2-y 1)- and 2-( 1,4-dioxo-1,3,4,6,11,11 a-hexahydro-2//-pyr-azino[l,2-i]isoquinolin-2-yl)acetamides, respectively (99MIP11). 

In SPPS, there are two main protecting groups commonly used for Ai -protection [3] ferf-butoxycarbonyl (Boc) [7] and 9-fluorenylmethoxycarbonyl (Fmoc) [8] (Fig. 2). 

Albericio F, Kneib-Cordonier N, Biancalana S, Gera L, Masada RI, Hudson D, Barany G. Preparation and application of the 5-(4-(9-fluorenylmethoxycarbonyl)aminomethyl-3, 5-dimethoxyphenoxy)-valeric acid (PAL) handle for the solid-phase synthesis of C-terminal peptide amides under mild conditions. J Org Chem 1990 55 3730-3743. 

Three generations of dendritic phosphines have been prepared from 3,5-diaminobenzoylglycine and 9-fluorenylmethoxycarbonyl-L-phenylalanine. The dendrimers were then attached to MBHA resin, treated with CH20 and Ph2PH, and converted to their Rh complexes. The polymer-supported complexes are excellent catalysts for the hydroformylation of alkenes, which could be recycled.283 The bidentate diphosphine A,A-bis-(P-(phosphabicyclo[3.3.1] nonan) methyl)aniline was prepared by phosphanomethylation of aniline. It forms a Rh-complex which is a highly regioselective catalyst in the hydroformylation of citronellene.284... 

Urge, L., Kollat, E., Hollosi, M., Laczko, I., Wroblewski, K., Thurin, J., and Otvos Jr., L. (1991) Solid-phase synthesis of glycopeptides synthesis of Na-fluorenylmethoxycarbonyl L-asparagine Nb-glyco-sides. Tetrahedron Lett. 32, 3445-3448. 

C.G. Fields, G.B. Fields, Minimization of tryptophan alkylation following 9-fluorenylmethoxycarbonyl solid-phase peptide synthesis, Tetrahedron Letters 34(1993)6661-6664. 

Fluorenylmethoxycarbonyl isothiocyanate (Fmoc-NCS) was synthesized according to a published procedure 1 it can also be purchased from Novabiochem. 

Krausz el al. have synthesised two series of amino acid porphyrinylsugar derivatives (Fig. 5). One of them involves the coupling of adequate glycoporphyrin derivatives, prepared by pyrrole/aldehyde condensation methodology, with 9-fluorenylmethoxycarbonyl-L-alanine (Fmoc-L-alanine) to give the tri-, di-, and mono-alanine glycoporphyrin derivatives 54—57 after the deprotection step the other series (58) involves a glucosylamino acid moiety instead of the alanine in their preparation.21,44... 

To overcome these difficulties in the selective deprotection and chain extension, several carboxyl-protecting groups, namely, allyl (16,32), benzyl (43,44), tert-butyl (42), 2-bromoethyl (45), 2-chloroethyl (45), heptyl (46), 4-nitrophenyl (47,48), and pentafluorophenyl (49) for L-serine/L-threonine have been introduced or applied. Similarly, amino-protecting groups for L-serine/L-threonine that have proved useful for the synthesis of glycopeptides are tm-butyloxycarbonyl (50), 9-fluorenylmethoxycarbonyl (43,44,48), 2-(2-pyridyl)ethoxycarbonyl (51), 2-(4-pyridyl)ethoxycarbonyl (44,52), and 2-triphenylphosphonioethoxycarbonyl (53). Some applications of these groups have been discussed in earlier reviews (7-11). 

Schultheiss-Reimann and Kunz(43) applied silver triflate as the promoting reagent for the reaction of 2,3,4-tri-O-benzyl-a-D-glucopyranosyl bromide (52) with V-(9-fluorenylmethoxycarbonyl)-L-serine benzyl ester to... 

FIGURE 3.11 Removal of the 9-fluorenylmethoxycarbonyl group by fcefa-elimination (Carpino Han, 1970). Deprotonation is achieved by hydroxide anion that generates dibenzofulvene or by piperidine that subsequently forms an addition product with the liberated moiety. 

C-D Chang, M Waki, M Ahmad, J Meienhofer, EO Lundell, JD Haug. Preparation and properties of N -9-fluorenylmethoxycarbonyl amino acids bearing tert. -butyl side chain protection. Int J Pept Prot Res 15, 59, 1980. 

L Lapatsanis, G Milias, K Froussios, M Kolovos. Synthesis of A-2,2,2,-(trichloro-ethoxy carbonyl)-L-amino acids and A-(fluorenylmethoxycarbonyl)-L-amino acids involving succinimidoxy anion as a leaving group in amino acid protection. Synthesis 671, 1983. 

A recently described approach involving zinc dust for eliminating acid allows acylation by 9-fluorenylmethoxycarbonyl chloride without dimer formation. The amino acid is dissolved in acetonitrile with the aid of hydrochloric acid, and zinc dust is added to destroy the acid and deprotonate the zwitter-ion, reducing the protons to gaseous hydrogen (Figure 3.16). Acylation is effected in the presence of zinc dust, which reduces the proton that is liberated by the reaction as soon it is formed. See Section 7.7 for another possible impurity in Fmoc amino acids.34,36-39... 

A Paquet. Introduction of 9-fluorenylmethoxycarbonyl, trichloroethoxycarbonyl, and benzyloxycarbonyl amino protecting groups into O-unprotected hydroxyamino acids using succinimidyl carbonates. Can J Chem 60, 976, 1982. 

E Atherton, M Caviezel, H Fox, D Harkiss, H Over, RC Sheppard. Peptide synthesis. Part 3. Comparative solid-phase synthesis of human P-endorphin on polyamide supports using t-butoxycarbonyl and fluorenylmethoxycarbonyl. 

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