Reaction of<i>N</i>-(α-Acetoxycinnamoyl)-<i>N</i>-hydroxy Derivatives of DL-Alanine Esters. Formation of Imidazolidinone and Its Transformations into Pyrrolidinedione and Oxazolidinone
作者:Yasuhiro Chigira、Mitsuo Masaki、Masaki Ohta
DOI:10.1246/bcsj.42.228
日期:1969.1
treatment with aqueoussodiumhydroxide and into methyl 5-benzylidene-2-methyl-4-oxo-2-oxazolidinecarboxylate (VII) by treatment with methanolic hydrogen chloride. VI was also derived from III or IV by treatment with sodiumhydroxide. N-(α-Acetoxycinnamoyl)-N-hydroxy-DL-alanine t-butyl ester prepared from N-hydroxy-DL-alanine t-butyl ester and II, was treated with aqueoussodiumhydroxide to give t-butyl
用 α-乙酰氧基肉桂酰氯 (II) 处理 N-苄氧基-DL-丙氨酸乙酯 (I) 得到 N-(α-乙酰氧基肉桂酰)-N-苄氧基-DL-丙氨酸乙酯 (III),然后用钠水溶液处理碳酸氢盐、哌啶或羟胺得到 N-苄氧基-N-(苯基-丙酮酰)-DL-丙氨酸乙酯 (IV)。III或IV与氨反应得到5-苯亚甲基-2-甲基-4-氧代-2-咪唑烷甲酸(V),通过处理将其转化为5-甲基-4-苯基-2,3-吡咯烷二酮(VI)用氢氧化钠水溶液和甲醇氯化氢处理转化为 5-亚苄基-2-甲基-4-氧代-2-恶唑烷甲酸甲酯 (VII)。VI 也通过用氢氧化钠处理从 III 或 IV 衍生而来。N-(α-乙酰氧基肉桂酰基)-N-羟基-DL-丙氨酸叔丁酯由N-羟基-DL-丙氨酸叔丁酯和II制备,
Syntheses and Reactions of<i>N</i>-(Phenylpyruvoyl) Amino Acids
作者:Yasuhiro Chigira、Mitsuo Masaki、Masaki Ohta
DOI:10.1246/bcsj.42.224
日期:1969.1
α-Ethoxy- and α-acetoxycinnamoyl chlorides were synthesized by treatments of α-ethoxy-and α-acetoxycinnamic acid with thionyl chloride and oxalyl chloride, respectively, and reactions of ammo acid esters with the cinnamoyl chlorides were investigated in order to seek for a synthetic method of N-(phenylpyruvoyl) amino acids. N-Hydroxy- or N-benzyloxy-Dl-alanine esters prepared from 2-bromopropionic esters and hydroxylamine or benzyloxyamine were treated with α-ethoxycinnamoyl chloride to give the corresponding N-(α-ethoxycinnamoyl) derivatives. Treatment of l-leucine ethyl ester with α-acetoxycinnamoyl chloride afforded N-(α-acetoxycinnamoyl)-l-leucine ethyl ester, the removal of the acetyl group from which was readily accomplished under mild, basic conditions, and N-(phenylpyruvoyl)-l-leucine ester was obtained. Treatment of the ester with ammonia yielded 3-benzylidene-6-isobutyl-2,5-piperazinedione.
Synthesis and antimicrobial properties of cephalosporin derivatives substituted on the C(7) nitrogen with arylmethyloxyimino or arylmethyloxyamino alkanoyl groups
7-aminocephalosporanic acid (7-ACA) derivatives substituted on the C(7) nitrogen with 2-(arylmethyloxyimino)propionyl (3a-f), 2-(arylmethyloxyamino)propionyl (4a-d) and (arylmethyloxyamino)acetyl (2a-d) moieties were synthesized by reaction of the appropriate acylating agents with 7-ACA protected as a t-butyl ester, followed by removal of the t-butyl protecting group. The new compounds, tested in vitro for their antimicrobial