An improved synthesis of (4S,5S)-2,2-dimethyl-4-phenyl-1,3-dioxan-5-amine

The title compound is prepared in 78% yield using an improved one-pot procedure which does not require final purification.     

Synthesis of (2S,4S)- and (2S,4R)-5-fluoroleucine and (2S,4S)-[5,5-2H2]-5-fluoroleucine

Syntheses of (2S,4S)- and (2S,4R)-5-fluoroleucine, and, and of (2S,4S)-[5,5-(2)H(2)]-5-fluoroleucine, have been completed. The methodology allows these compounds to be prepared in sufficient quantities for incorporation by solid-state protein synthesis into strategic sites in proteins for folding studies. X-ray structures of the epimers and have been obtained and show the presence of conformational isomerism. The torsion angles between the F-C bond and the main chain are compared with values found in a mutant of the protein ubiquitin in which (2S,4S)-5-fluoroleucine replaces leucine residues 50 and 67 in the native protein.     

手性5-(R)-(1′R,2′S,5′R)-孟氧基丁内酯并[3,4-b]-2(S)-6(R)-1-N-环己基氮杂环丙烷的合成及晶体结构

环己胺与手性元5-(R)-(1′R,2′S,5′R)-孟氧基-3-溴-2(5H)-呋喃酮的不对称M ichael加成/分子内亲核取代反应,得到含有两个新手性中心的氮杂环丙烷/稠合丁内酯标题化合物。对其进行了谱学表征和X-射线单晶衍射测定。标题化合物分子式为C20H33NO3,M r=335.47,三斜晶系,P1空间群,晶胞参数:a=5.438(11)。A,b=8.117(2)。A,c=11.572(2)。A,α=96.84(3)°,β=94.48(3)°,γ=101.86(3),°V=493.5(2)。A3,Z=1,D c=1.129g/cm3,R=0.0867,wR=0.2344。     

Synthesis of 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-4-ones

A Darzens condensation of α-chloroacetamide with aromatic aldehydes furnished a series of 3-aryl-2,3-epoxypropionamides, which were further converted to 5-[bromo(aryl)methyl]-2,2-dimethyl-1,3-oxazolidin-2-ones.     

Synthesis and Crystal Structure of (4R, 5R)(5-Hydroxymethyl-2,2-dimethyl- [1,3]dioxolan-4-yl)-bis-(4-methoxy-phenyl)-methanol

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅα ,α ,α′,α′ ｔｅｔｒａａｒｙｌ 1 ,3 ｄｉｏｘｏｌａｎｅ 4,5 ｄｉｍｅｔｈａｎｏｌｓ (ＴＡＤＤＯＬＳ)ｄｉｏｌｓｗｈｉｃｈａｒｅｒｅａｄｉｌｙａｖａｉｌａｂｌｅｆｒｏｍａｌｋｙｌｔａｒｔｒａｔｅｓ ,ｈａｖｅｂｅｅｎｗｉｄｅｌｙｕｓｅｄａｓｃｈｉｒａｌｌｉｇａｎｄｓｉｎｅｎａｎｔｉｏｓｅｌｅｃｔｉｖｅａｄｄｉｔｉｏｎｒｅａｃｔｉｏｎｓｏｆｃａｒｂｏｎ ｃｅｎｔｅｒｅｄｎｕｃｌｅｏｐｈｉｌｅｓｔｏａｌｄｅｈｙ ｄｅｓ[1 ] ,ｉｎ [2 +2 ]ｃｙｃｌｏａｄｄｉｔｉｏｎｓ[2 ] …     

新型(4R,5R)-2-苯基-1,3-二氧戊环-4,5-二(2-吡啶甲氧基)甲烷的合成

设计并合成了一种新型以L-酒石酸为手性源的具有C2-对称轴的吡啶衍生物手性配体——(4R,5R)-2-苯基-1,3-二氧戊环-4,5-二(2-吡啶甲氧基)甲烷,其结构经1H NMR和MS表征。     

1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并(口恶)嗪)基]乙烷的合成及晶体结构

N-取代的3,4-二氢-1,3-苯并(口恶)嗪具有生物活性,是潜在的安定剂和镇静剂,还是制备酚醛树脂的潜在中间体[1-3].一般以酚、伯胺和甲醛为原料,通过Mannish缩合反应来制备[4].本文通过2,4-二叔丁基苯酚、乙二胺和甲醛反应,合成了亚乙基桥联的双(口恶)嗪,X-射线单晶衍射测定了它的晶体结构.     

5-[5-R-furfurylidene]-2,2-dimethyl-1,3-dioxane-4,6-diones 6. Synthesis,structure, and properties of substituted furylimino- and furfurylidenephosphoranes. Molecular and crystal structure of N-[5-(2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)methyl-2-furylimino(triphenyl)phosphorane

Furylimino- and furfurylidenephosphoranes have been synthesized by sequential conversions of 5-unsubstituted and 5-methylfurfut),Iidetiedio.yanediones. The ylide fragment linked directly with the furfurylidenedioxanedione residue displays strong electron-donating properties, as a result of which resonance occurs in the system of conjugated bonds. The molecular and crystal structure of the iminophosphorane was studied by x-ray structural analysis and the resonance of the bonds in the molecule was confirmed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 335–344, March, 1994.     

1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并嗪)基]乙烷的合成及晶体结构

~~1,2-二[3-(6,8-二叔丁基-3,4-二氢-1,3-苯并噁嗪)基]乙烷的合成及晶体结构@徐小平$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @姚英明$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @赵艺萍$江阴市长泾中学!江苏江阴214411 @张勇$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州215006 @沈琪$苏州大学化学化工学院!江苏省有机合成重点实验室,江苏苏州2150061,2-二[3-(6,8-二叔丁基.3,4-二氢-1,3-苯并噁嗪)基]乙烷;;合成;;晶体结构[1] Neuvonen K,Pihlaja K. J. Chan. Soc…