Linkers Based on Benzyloxycarbonyl Z

In order to allow attachment of an amine to a hydroxymethyl-modified support, the 

Polymer-bound amine 5 is obtained by treatment of 4 with HNR R. After combi- 

Cleavage of 3 to yield the amine 6 Loaded resin 5 (50 mg, 35 pmol) was stirred with CH2CI2 (1 mL) and TFA (1 mL) at room temperature. After 3 h, MeOH (1 mL) was added, and the resin was filtered off and washed with MeOH, CH2CI2, and MeOH (2x2 mL). The filtrate was concentrated under vacuum to give 13 mg (85% yield at 0.8 mmol g loading) of a white solid, which was identical to authentic Phe-Val-Phe-OMe (6) by IR, MS, and HPLC. 

The acid-labile carbamate linkage of type 5 has also been apphed to the paraUel synthesis of a thiazolidinone library of type 12 (Fig. 2) [22], Apphcation of trityl-based resins (see Section 2.2.2.6) for this reaction sequence was not possible as the 

Recently, benzyloxycarbonyl-based linkers have been described for the synthesis of carbolines of type 13 [23], substituted benzimidazolones 14 [24], and quinoxa-lines 15 [25] (Fig. 3). 

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