“…Then, 5-hydroxypyrazole 5 was treated with POCl 3 and DMF to give 4-formyl-5-chloropyrazole 6 in 87% yield. 17 Subsequently, the substitution of 4-formyl-5-chloropyrazole 6 with phenols, benzenethiols, t-BuSH, and MeSNa under basic conditions, produced aldehydes 7a-7n (Scheme 2), 10a-10d (Scheme 3) in satisfactory yields. 18 Aldehydes 7a-7n, 10a-10d were then converted to the corresponding oximes 8a-8n, 11a-11d by hydroxylamine under basic conditions, 19 and further etherification of oximes 8a-8n, 11a-11d with the intermediate 4 under base promoting conditions generated the title compounds 9a-9n (Scheme 2), 12a-12d (Scheme 3).…”