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10957 Amino-dPEG 8-t-boc-hydrazide

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CAS: 1334169-96-8

Item Name: Amino-dPEG 8-t-boc-hydrazide

Item #: 10957

Mol. Wt.: 555.66;

single compound dPEG Spacer is 30 atoms and 35.9 A approx.

10957 Amino-dPEG 8-t-boc-hydrazide

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$250.00

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CAS: 1334169-96-8
Item Name: Amino-dPEG 8-t-boc-hydrazide
Item #: 10957
Mol. Wt.: 555.66;
single compound dPEG Spacer is 30 atoms and 35.9 A approx.
Product Features and Benefits: Carboxyl or carbonyl reactive dPEG 4 pegylation reagent with a carbonyl reactive hydrazide (protected as the t-boc) dPEG pegylation spacer is hydrophilic, highly water soluble and non-immunogenic. The t-boc protected hydrazide is not particularly water soluble, but is very soluble in most organic solvents. However its inherent hydrophilicity is high once incorporated as a conjugated system t-Boc group is easily removed with TFA (25% TFA in CH2Cl2, ice bath/0oC; can be done neat r.t., 10 min.) t-Boc group provides a potentially powerful purification handle due to its hydrophobicity when initially incorporated into the reaction scheme.. This applies best when using normal phase (e.g., silica gel) chromatography. Protocols: The following are general use guidelines for reaction with: a. An active ester: Find a solvent in which active ester is soluble (methylene chloride is a preferred solvent) and dissolve the ester in the dry solvent, add triethylamine, then add the amine, either neat or drop wise as a solution in the reaction solvent. Use at least a 10% excess of all reagents relative to the active ester. This can be carried out at ambient temperatures. b. A free acid: i) generate the active ester in situ with EDC and NHS or HOBt, then add the triethylamine, followed by the amino-dPEG 4 t-butyl ester; or ii) combine the acid, NHS or HOBt, TEA, and the amino-dPEG 4 t-butyl ester, and add a solution of the EDC. Use at least a 10% excess of reagents relative to the acid. Note: Carbodiimides other than EDC can be used, but the water soluble and polar nature of the by-products makes work-up very efficient with EDC. DCC is also very good, if one is able to remove all of the DCU. These reactions are best carried out at 10 to -0oC. The reactions all need to be monitored by chromatography, TLC, or HPLC. Subsequently the t-boc can be removed using standard methods, e.g., with either TFA or HCl.