Highly Symmetrical Amino Acid-Derived N,N′-Diacylated Sulfodiimines

Abstract

A mild and efficient method for the coupling of sulfodiimines with N-protected amino acids has been developed, yielding the corresponding N,N′-diacylated sulfodiimines with up to 94% yield.

Key words

coupling - amino acids - acylations - peptides - sulfodiimines - asymmetric synthesis

References

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12

In this case, the meso-product resulting from an epimerization would possess two diastereotopic methyl groups. Those would be in rather different chemical and electronic environments and, therefore, two different chemical shifts would be likely to occur in the ¹H NMR spectrum.