*3.7. Tosylation of Azide Diol (S)-***8**

*(S)-3-Azido-2-hydroxypropyl 4-methylbenzenesulfonate* ((*S*)-**8***-* ). To a solution of (*S*)-**8** (23.4 mg, 0.20 mmol) in CH3CN (0.80 mL) was added pyridine (23.7 mg, 0.30 mmol) and TsCl (57.2 mg, 0.30 mmol) at room temperature. After stirring for 10 h at the same temperature, the reaction was quenched with H2O, and the resulting mixture was extracted with AcOEt. The combined organic layers were washed with brine, dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/AcOEt = 2/1) to afford (*S*)-**8***-* (30.3 mg, 0.112 mmol, 56% yield) as a colorless oil; [α]D<sup>27</sup> −17.5 (*<sup>c</sup>* 1.00, AcOEt) for 94% ee; 1H NMR (400 MHz, CDCl3): *δ* 7.81 (d, *J* = 8.3 Hz, 2H), 7.38 (d, *J* = 8.3 Hz, 2H), 4.09–3.98 (m, 3H), 3.43 (dd, *J* = 12.9, 4.6 Hz, 1H), 3.38 (dd, *J* = 12.7, 5.4 Hz, 1H), 2.47 (s, 3H), 2.40 (d, *J* = 5.4 Hz, 1H); 13C{1H} NMR (100 MHz, CDCl3): *δ* 145.4, 132.3, 130.0, 128.0, 70.5, 68.5, 52.7; IR (ATR): 3462, 2100, 1597, 1352, 1173, 1096, 982 cm−1; HRMS (EI) *m*/*z*: [M]<sup>+</sup> calcd for C10H13N3O4S 271.0627, found 271.0622; HPLC analysis: Chiralpak AY-H, hexane/EtOH = 6/1, flow rate 1.0 mL/min, wavelength 254 nm, *t*<sup>R</sup> 28.9 min (minor) and 31.3 min (major).

**Supplementary Materials:** The following supporting information can be downloaded at: https:// www.mdpi.com/article/10.3390/molecules27249025/s1, Figures S1–S10: Copies of 1H and 13C{1H} NMR spectra of compounds **2–12**; Figures S11–S15: Chiral HPLC chromatogram of compounds **2**, **5**, **6**, **7**, and **8***-* .

**Author Contributions:** Conceptualization, O.O.; methodology, O.O.; investigation, K.Y., K.M., M.U. and Y.T.; writing—original draft preparation, K.Y.; writing—review and editing, O.O., M.K. and K.Y.; visualization, K.Y., K.M., M.U. and Y.T.; supervision, O.O.; project administration, K.Y. and M.K.; funding acquisition, O.O., M.K. and K.Y. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded in part by JSPS Grant-in-Aid for Scientific Research (22K06528, 22K15255, and 19K05459) and a grant from the Japan Soap and Detergent Association.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** The data presented in this study are available in Supplementary Material.

**Acknowledgments:** The spectral data were collected with the research equipment shared in the MEXT Project for promoting public utilization of advanced research infrastructure (Program for Supporting Introduction of the New Sharing System JPMXS0422500320).

**Conflicts of Interest:** The authors declare no competing financial interests.

**Sample Availability:** Samples of the compounds are not available from the authors.
