Reaction of phenyl acetic acid derivatives with thiosemicarbazide in the presence of POCl3 afforded 5-(4-bromobenzyl)-1,3,4-oxadiazole-2-amine 1 and 5-(3-nitrophenyl)-1,3,4-oxadiazole -2-amine 2. Acylation of the amino group of oxadiazoles 1 and 2 with some acid chlorides such as methyl 4-(chlorocarbonyl) benzoate, 3-nitrobenzoyl chloride, 4-methoxy-benzoyl chloride, 4-isobutylbenzoyl chloride and chloroacetyl chloride yielded the acylated compounds 3-8. Cyclization of acetamides 7 and 8 by reaction with ammonium thiocyanate gave the thiazolidinones 9 and 10. Coupling of chloroacetamide 7 with two mercaptothiazoles gave coupled heterocyclic derivatives 11 and 12. Coupling of amino-oxadiazole 1 with N-Boc-glycine and N-Boc-phenylalanine lead to the formation of 16 and 17 respectively. All compounds were screened for their antibacterial activity against Salmonella typhi where compounds 3, 4, 10, 11 and 15 showed significant activity. Structures of the new synthesized compounds were confirmed using the spectral analysis such as IR, 1H NMR and 13C NMR and mass spectrometry.

中文翻译：

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合成新型2-氨基-1,3,4-恶二唑衍生物，具有抗鼠伤寒沙门氏菌活性。

在POCl3存在下，苯乙酸衍生物与硫代氨基脲反应，得到5-（4-溴苄基）-1,3,4-恶二唑-2-胺1和5-（3-硝基苯基）-1,3,4-恶二唑-2-胺2。用一些酰氯如4-（氯羰基）苯甲酸甲酯，3-硝基苯甲酰氯，4-甲氧基-苯甲酰氯，4-异丁基苯甲酰氯和氯乙酰氯酰化恶二唑1和2的氨基酰基。酰化化合物3-8。通过与硫氰酸铵反应将乙酰胺7和8环化，得到噻唑烷酮9和10。氯乙酰胺7与两个巯基噻唑的偶合得到偶联的杂环衍生物11和12。氨基-恶二唑1与N-Boc-甘氨酸和N-Boc-偶合。苯丙氨酸分别导致16和17的形成。筛选所有化合物对伤寒沙门氏菌的抗菌活性，其中化合物3、4、10、11和15表现出显着活性。使用诸如IR，1 H NMR和13 C NMR的光谱分析和质谱法确认了新合成的化合物的结构。