Einige Derivate der <i>d</i>‐Galaktose und <i>d</i>‐Fucose

Iselin, B.; Reichstein, T.

doi:10.1002/hlca.19460290303

Cited by 32 publications

(19 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, independently-synthesized 22 was rapidly (within 5 min) and almost quantitatively converted into 15 (isolated yield, 94%) under the same conditions, and no trace of 14 was detected (7). Similarly, the 3,4-anhydrohexopyranoside 23, obtainable from 5 by action of base, reacted (7) with LTBH in the same way, to give methyl 3,6-dideoxy-a-L-lyxohexopyranoside (24) in the same yield and without any 13.…”

Section: Prelimitzary Mechanistic Considerationsmentioning

confidence: 93%

The formation of branched-chain deoxypentofuranosides by ring contraction in the reductive desulfonyloxylation of hexopyranoside p-toluenesulfonates

Baer¹,

Astles²,

Chin³

et al. 1985

Can. J. Chem.

View full text Add to dashboard Cite

. 63, 432 (1985). Several methyl 6-deoxy-, 6-deoxy-6-halo-, and 6-0-p-tolylsulfonylhexopyranoside 2-and 4-p-toluenesulfonates reacted readily with lithium triethylborohydride in boiling tetrahydrofuran under reductive dcsulfonyloxylation at C-2 and C-4, respectively, and with reduction at C-6 whcre applicable. The desulfonyloxylations procceded with ring contraction to furnish, in 40-60% isolated yields, new branched-chain pentofuranoside derivatives, namely, methyl 2.5-dideoxy-2-C-(hydroxymethyl)pentofuranosidcs having the a-~-xj~lo, a-D-xj~lo, and a-D-ribo configurations (from 2-tosylatcs), and methyl 3.5-dideoxy-3-C-(hydroxymethyl)pentofuranosides having the a-D-arabitzo and a-D-ribo configurations (from 4-tosylatcs). In some of the reactions, reductively desulfonyloxylated but unrearranged products were formed in addition. Methyl 4,6-0-benzylidene-2,3-di-O-p-tolylsulfonyl-a-~-gaactopyranoside reacted by partial de-0-sulfonylation and partial desulfonyloxylation, with and without ring contraction, to give methyl 3.5-0-benzyIidcne-2-deoxy-2-C-(hydroxymethyl)-a-~-/~~xo-pentofuranoside, methyl 4,6-0-benzyIidene-3-deoxy-a-~-/yxo-hexopyranosidc, and the parent 2.3-diol.

show abstract

Section: Prelimitzary Mechanistic Considerationsmentioning

confidence: 93%

The formation of branched-chain deoxypentofuranosides by ring contraction in the reductive desulfonyloxylation of hexopyranoside p-toluenesulfonates

Baer¹,

Astles²,

Chin³

et al. 1985

Can. J. Chem.

View full text Add to dashboard Cite

show abstract

“…None of the presently available protecting groups is entirely satisfactory. For example, even the HF-stable S-acetamidomethyl (Acm) group (27) for cysteine and S-oxide group (28) for methionine are not compatible with the organomercurial Cys-Met tactic. The Cys(Acm) residues are stable during solid-phase synthesis, HF cleavage, thiol reduction, and CNBr treatment; the Met(O) residues are stable during synthesis, HF cleavage, binding to organomercurial-agarose and CNBr cleavage.…”

Section: Resultsmentioning

confidence: 99%

Affinity purification of synthetic peptides.

Krieger¹,

Erickson²,

Merrifield³

1976

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

A general strategy and a specific tactic for affinity purification of polypeptides synthesized on solid supports are desbribed and demonstrated. The desired peptide chains were distinguished from terminated peptide chains before removal from the support by attachment of an affinity reagnet (cysteinyl-methionine) bearing an affinity group (thiol) and a binding group (carboxylic acid). After cleavage from the synthetic support, the affinity-labeled peptides (Cys-Met-peptides) were bound to an affinity receptor (organomercurial-agarose) and thus separated from terminated peptides and all other peptides lacking the affinity group. The desired synthetic peptide was obtained by separation of the affinity reagent (loss of Cys-Met by cyanogen bromide cleavage). This general affinity purification strategy is independent of the length or amino acid sequence of the desired peptide. After assembly of ribonuclease-(111-124)-tetradecapeptide, using radiolabeled acetic anhudride for termination of uncoupled in termediates, essentially all (greater than 98.5%) of the acetylated delection peptides were removed by employing the organomercurial Cys-Met tactic. Similarly, the purity of crude synthetic histone H4-(1-37)-heptatriacontapeptide was increased six-fold by using this tactic to remove terminated peptides. A related dimeric Cys-Met tactic is outlined for affinity purification of peptides containing internal cysteine and methionine residues.

show abstract

“…The deprotected peptide was treated with diluted ammonia at pH 10 for 15 min in order to reverse the N+O shift (38) and then incubated with DTT at pH 6.5 to reduce the Met(0) (39,40) possibly formed during manipulation. The treated product was purified by gel-filtration on Sephadex C-25, followed by ion-exchange chromatographies on CM-cellulose and DEAEsepharose.…”

Section: Z(0me)-his-ser(bz1)-asp-gly-leu-phe-mentioning

confidence: 99%

ChemInform Abstract: STUDIES ON PEPTIDES. CXIII. SYNTHESIS OF THE HEPTACOSAPEPTIDE AMIDE CORRESPONDING TO THE ENTIRE AMINO ACID SEQUENCE OF CHICKEN SECRETIN

Kiyama¹,

Fujii²,

Yajima³

et al. 1984

Chemischer Informationsdienst

View full text Add to dashboard Cite

The heptacosapeptide amide corresponding t o the entire amino acid sequence of chicken secretin was synthesized by assembling four peptide fragments followed by deprotection with thioanisole-mediated trifluoromethanesulfonic acid in TFA. The deprotected peptide was purified by gel-filtration on Sephadex (3-25, followed by ionexchange chromatographies on CM-cellulose and DEAE-Sepharose. Synthetic peptide stimulated the flow of pancreatic alkaline juice and decreased systemic blood pressure in rats.

show abstract

Einige Derivate der d‐Galaktose und d‐Fucose

Cited by 32 publications

References 4 publications

The formation of branched-chain deoxypentofuranosides by ring contraction in the reductive desulfonyloxylation of hexopyranoside p-toluenesulfonates

The formation of branched-chain deoxypentofuranosides by ring contraction in the reductive desulfonyloxylation of hexopyranoside p-toluenesulfonates

Affinity purification of synthetic peptides.

ChemInform Abstract: STUDIES ON PEPTIDES. CXIII. SYNTHESIS OF THE HEPTACOSAPEPTIDE AMIDE CORRESPONDING TO THE ENTIRE AMINO ACID SEQUENCE OF CHICKEN SECRETIN

Contact Info

Product

Resources

About