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The reaction of 5-am ino-3-aryl-l-phenylpyrazoles (la-d) with formaldehyde and secondary amines in boiling ethanol gave the corresponding 4-alkylaminomethyl derivatives (2a-f) and bis-(4-pyrazolyl)methane (4a,b) as byproduct. Such reaction with primary aliphatic and aro matic amines at room temperature afforded 1,3,5-trisubstituted (5a-h) and 1,3.5,7-tetrasubstituted tetrahydropyrazolo[3,4-d]pyrimidines (8a-k) respectively in good yield. Similarily, the Mannich reaction of 5-m ercapto-3-phenyl-l,2,4-triazole (9) with secondary amines, in boiling ethanol, and primary aromatic amines, at room temperature, gave 2 -substituted aminomethyl derivatives (lOa-c) and (14a-g) respectively,while with primary aliphatic amines, p-toluidine and p-anisidine,at room temperature,and with other primary aromatic amines, in boiling etha nol, afforded the cyclized products l,2,4-triazolo[3,4-b]thiadiazines (13a-e); (15f,g) and (15a-e), respectively. * Reprints requests to Dr. Z. A. Hozien. phenylpyrazoles (la-d) and 5-m ercapto-3-phenyl-1,2,4-triazole (9) as bifunctional nucleophiles with both secondary and prim ary amines. T reatm ent of la-d with m orpholine or piperidine and form aldehyde in boiling ethanol afforded 5-am ino-3-aryl-l-phenyl-4-m orpholinom ethyl/ piperidinom ethylpyrazoles (2 a-f) which revealed the C4 center is m ore nucleophilic than the am ino group at C5. The IR spectra of 2a-f displayed the N H 2 stretching bands at 3380-3200 cm -1. The !H N M R spectra of 2a-f lacked the H -C 4 p ro to n (at <3 5.6 ppm ) [14] and show ed the -N H 2 signal at d 4.85-4.55 ppm , in addition to the o th e r p roton which appeared at the expected chem ical shifts, Table IV. Side reaction products w ere obtained, in som e cases, due to the condensation of la,b with form aldehyde, which was identified as 4a,b. The structures of 4a-b w ere established for the reaction products based on their analytical and spectral data. The IR spectra lacked N H 2 signals. The !H N M R spectrum of 4a show ed two doublets at d 3.85 (J = 16 H z) and d 4.56 (J = 16 H z) integrated for 4 protons attrib u ted to the vinylic protons, in addition to a singlet at d 4.62 ppm a ttrib u te d to the o th er m ethylene protons. The form ation of 4a,b m ay be rationalized in term s of the initial form ation [15-16] of 3 fol lowed by condensation with form aldehyde to give 4. The 13C N M R spectrum of 4a was in accordance

The reaction of 4,5‐diphenylimidazol‐2‐thione (1) with aromatic ketones 2a‐i using the acidified acetic acid method afforded the 4,5‐diphenyl(2‐imidazolylthio)acetophenones 3a‐h in good yields. While, the cyclized product 4i was obtained directly upon reaction of 1 with α‐acetyl naphthalene. Compounds 3a‐h were cyclized directly to the corresponding 3‐aryl‐5,6‐diphenylimidazo[2,1‐b]thiazoles (4a‐c) and (4e‐h). In the same manner the reaction of 1 with aliphatic and/or alicyclic ketones gave the 3‐(4,5‐diphenyl‐2‐imidazolylthio)acetone derivatives 5a‐d, 2‐(4,5‐diphenylimidazolylthio)cycloalkanones 8a,d and the tricyclic compounds 9b‐c respectively. The cyclized compounds 6a‐d and 9a,d were obtained by cyclization of 5a‐d and 8a,b respectively. Oxidation of 1 gives the corresponding bis(4,5‐diphenyl‐2‐imidazolyl)‐disulfide (10) in 90% yield. Some of the synthesized compounds were tested for antifungal and antibacterial activity.