Integramide A is a 16‐amino acid peptide inhibitor of the enzyme HIV‐1 integrase. We have recently reported that the absolute stereochemistries of the dipeptide sequence near the C terminus are L‐Iva14‐D‐Iva15. Herein, we describe the syntheses of the natural compound and its D‐Iva14‐L‐Iva15 diastereomer, and the results of their chromatographic/mass spectrometric analyses. We present the conformational analysis of the two compounds and some of their synthetic intermediates of different main‐chain length in the crystal state (by X‐ray diffraction) and in solvents of different polarities (using circular dichroism, FTIR absorption, and 2D NMR techniques). These data shed light on the mechanism of inhibition of HIV‐1 integrase, which is an important target for anti‐HIV therapy.