[C:1]1([C:7]#[C:8][C:9]2[CH:18]=[CH:17][CH:16]=[CH:15][C:10]=2[C:11](OC)=[O:12])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[NH2:19][OH:20].[OH-].[K+]>C1COCC1.CO>[OH:20][NH:19][C:11](=[O:12])[C:10]1[CH:15]=[CH:16][CH:17]=[CH:18][C:9]=1[C:8]#[C:7][C:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1In a 100 mL round-bottomed flask was added methyl 2-(phenylethynyl)benzoate 36 (157 mg, 0.665 mmol) in THF (1.33 mL) and MeOH (1.33 mL) and the solution was cooled to 0° C. Then, a 50% aqueous solution of hydroxylamine (2195 mg, 33.2 mmol) was added followed by a 4M aqueous solution of KOH (0.33 mL, 1.329 mmol) and the resulting colorless solution was stirred at 0° C. and allowed to slowly warm to rt for 20 h. The reaction mixture was partitioned between EtOAc and H2O. The aqueous layer was extracted with EtOAc (2×) and the combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated in vacuo. The yellow oil was crystallized in Et2O and the filtrate was evaporated and triturated again in Et2O. The solids were combined to afford title compound 37 (67 mg, 43% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ (ppm): 10.98 (s, 1H), 9.20 (s, 1H), 7.61 (d, J=7.4 Hz, 1H), 7.55-7.43 (m, 814). LRMS (ESI): (calc.) 237.25 (found) 238.2 (MH)+
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