Synthesis of the C-terminal half of thymosin α1 by the polymeric reagent method

In this report we further show the utility and efficiency of polymer-bound 1-hydroxybenzotriazole (PHBT) as an almost ideal support for the polymeric reagent method of peptide synthesis. This was demonstrated by the synthesis of thymosin α₁ (15–28), in which two suitably blocked segments, Boc-Asp (OtBu)-Leu-Lys (2Cz)-Glu (OBzl)-Lys (2Cz)-Lys (2Cz)-OH ( 3 ) and Boc-Glu (OBzl)-Val-Val-Glu (OBzl)-Glu (OBzl)-Ala-Glu (OBzl)-Asn-OBzl ( 2 ), were prepared entirely by utilizing PHBT activation for each coupling step. After appropriate deblocking of 2 , segments 2 and 3 were coupled by the DCC-HOBT method, followed by complete deblocking and ion-exchange chromatographic purification, affording the C-terminal half of thymosin α₁, H-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH ( 1 ).     

Febrile Response to Bacterial Pyrogens in Leukemia

1. The intravenous injection of 50,000,000 dead typhoid-paratyphoid bacilliproduced a greater febrile reaction in nonbeukemics than in patients withchronic lymphocytic leukemia.

2. These results suggest that granulocytes may contribute to the productionof the fever that follows injection of bacterial pyrogens.

Submitted on July 12, 1959 Accepted on February 18, 1960