摘要:
Urethane-protected NCAs and MTAs are prepared by reacting an NCA or NTA with a haloformate in an inert diluent, under anhydrous conditions and in the presence of a tertiary nitrogen-containing base having an atom or functional group sufficiently electron rich and positioned relative to the nitrogen of said base so as to render said atom or group capable of complexing with the H--N
摘要:
The invention relates to urethane-protected amino acid-N-carboxyanhydride and N-thiocarboxyanhydride compounds which are useful in peptide, polypeptide and protein synthesis. Disclosed herein is the preparation and use of these novel compounds.
摘要:
Metabolically-acceptable, surgical adhesives are prepared from polyisocyanates having the structral formula: ##STR1## wherein R is a polyvalent aliphatic radical of about 1 to 10 carbon atoms or a polyvalent aromatic radical of 6 to about 24 carbon atoms;A is C, S or P;Z is O or S;Y is 1 when A is C or P, and 2 when A is S;n is 1 or 2;p is at least 1;q is 0 or 1, with the proviso that when A is carbon or sulfur, q is 0;r is 0 or 1, with the proviso that when A is carbon or sulfur, r is 0;X is a residue of an organic compound having active hydrogen-containing groups; andX' is a residue of an organic compound having at least 1 active hydrogen-containing group.
摘要:
An apparatus for synthesizing a polypeptide chain on an insoluble solid support in a continuous flow reactor by performing a series of stepwise coupling reactions under high pressure is disclosed. A deprotecting agent reservoir, a solvent reservoir, a neutralizing solution reservoir, and a plurality of amino acid reservoirs are provided. Each reservoir can be selectively coupled to the reactor and a source of high pressure inert gas or an appropriate pump can be used to force the fluids as needed to the reactor. The reactor also includes a recycle loop whereby the amino acid from a particular reservoir can be recycled through the reactor under high pressure.
摘要:
In the synthesis of a polypeptide chain wherein an N.sup..alpha. -urethane-protected amino acid mixed anhydride is coupled with an amino-unprotected second amino acid, the improvement comprising conducting said coupling at room temperature or above. This method provides rapid, essentially quantitative reactions without the necessity for reduced temperatures. The method is particularly useful in the solid-phase synthesis of peptides where shortened coupling cycles and improved yields of substantially pure products are obtained.
摘要:
In the method for the synthesis of a polypeptide chain on an insoluble solid support wherein an amino acid is introduced into a reactor packed with an insoluble solid support containing substituent groups reactive with said amino acid, coupling said amino acid to said support by condensation reaction with said reactive substituent groups, introducing a second similar or dissimilar amino acid into said reactor and coupling said second amino acid to said first amino acid and repeating the process until the desired polypeptide is obtained, the improvement wherein a high pressure flow system is used and the reaction pressure in said reactor during said synthesis is at least 200 psi up to 10,000 psi or more, in order to obtain rapid reactions and quantitative yields of the desired products.
摘要:
Homopolymers and copolymers containing the amino acid 3,4-dihydroxy-L-phenylalanine (dopa) have been prepared via the synthesis of a protected N-carboxyanhydride (NCA) of the amino acid. These dopa-containing polymers have many uses as in the treatment of Parkinsonism, as drug delivery systems, antioxidants, and fibers and in the production of non-thrombogenic substrates.
摘要:
Compounds of the formula: ##STR1## wherein n is 0 or 1, R is lower alkyl (substituted or unsubstituted), R' is H or lower alkyl, and R" is a branched alkyl, alkyl-cycloalkyl, cycloalkyl, polycycloalkyl (poly=2 or more, fused or non-fused), phenyl or alkyl-substituted phenyl, and physiologically acceptable cationic and acid addition salts thereof, which compounds are potent sweeteners. These derivatives of gem-diaminoalkanes are many times sweeter than sugar and are free from undesirable flavor qualities. Furthermore, they possess an unanticipated high degree of solubility compared with known synthetic sweeteners. In addition, the compounds possess high stability so that they can be used in all types of beverages and in conventional food processing. Sweetening compositions and sweetened edible compositions of these compounds are also provided.
摘要:
Provided are reagents and methods useful for the synthesis of guanidinylated compounds. Also provided are methods for assaying molecules, including guanidinylated molecules that modulate viral infection and replication.