3.2.1. Infrared Spectral Analysis

In the IR spectrum of venetoclax hydrate (Figure 2) the most diagnostic bands are associated with the shoulder of an OH band of water in the 3700–3400 cm−<sup>1</sup> region, N–H stretching vibrations (3364 and 3303 cm−<sup>1</sup> ), C–H stretching vibrations of the benzene rings (3141 and 3105 cm−<sup>1</sup> ), C–H stretching vibrations of CH<sup>2</sup> and CH<sup>3</sup> groups (2917 and 2842 cm−<sup>1</sup> ), C=O stretching vibration of an amide bond (1677 cm−<sup>1</sup> ), and stretching

cm−1), C=O stretching vibration of an amide bond (1677 cm−1), and stretching vibrations

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vibrations that are probably associated with C=C aromatic rings, the –NO<sup>2</sup> group, and the –SO<sup>2</sup> group (1607, 1569, 1521, 1362, 1346 and 1141 cm−<sup>1</sup> ). that are probably associated with C=C aromatic rings, the –NO2 group, and the –SO2 group (1607, 1569, 1521, 1362, 1346 and 1141 cm−1). stretching vibrations (3364 and 3303 cm−1), C–H stretching vibrations of the benzene rings (3141 and 3105 cm−1), C–H stretching vibrations of CH2 and CH3 groups (2917 and 2842

**Figure 2.** IR spectrum of **VEN·H2O**. **Figure 2.** IR spectrum of VEN·H2O. **Figure 2.** IR spectrum of **VEN·H2O**.

3.2.2. Raman Spectral Analysis 3.2.2. Raman Spectral Analysis 3.2.2. Raman Spectral Analysis

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The Raman spectrum of venetoclax hydrate (Figure 3) displays CH stretching of unsaturated carbons in the region above 3000 cm−1, while CH stretching of saturated carbons populates the region from 3000 to 2840 cm−1. The most diagnostic bands in the Raman spectrum are located at 1678 cm−1 (C=O stretch of an amide bond) and a very strong aryl The Raman spectrum of venetoclax hydrate (Figure 3) displays CH stretching of unsaturated carbons in the region above 3000 cm−<sup>1</sup> , while CH stretching of saturated carbons populates the region from 3000 to 2840 cm−<sup>1</sup> . The most diagnostic bands in the Raman spectrum are located at 1678 cm−<sup>1</sup> (C=O stretch of an amide bond) and a very strong aryl C=C stretch 1607 cm−<sup>1</sup> . The Raman spectrum of venetoclax hydrate (Figure 3) displays CH stretching of unsaturated carbons in the region above 3000 cm−1, while CH stretching of saturated carbons populates the region from 3000 to 2840 cm−1. The most diagnostic bands in the Raman spectrum are located at 1678 cm−1 (C=O stretch of an amide bond) and a very strong aryl C=C stretch 1607 cm−1.

**Figure 3.** Raman spectrum of **VEN·H2O**. **Figure 3.** Raman spectrum of **VEN**·**H2O**.

3.2.3. Thermal Analyses

3.2.3. Thermal Analyses
