6-氨基己酸及2-氨基乙磺酸C_(60)加成物的合成及溶解性

Synthesis and Solubility of 6-Aminohexanoic Acid and 2-Aminoethanesulfonic Acid C_(60) Adducts

水溶性Fullerenes(C60)衍生物的制备对于C60的生物学研究具有十分重要的意义.氨基酸与C60的胺化反应可得到水溶性的氨基酸C60衍生物.以C60与过量6-氨基己酸或2-氨基乙磺酸(摩尔比为1∶10)于80℃搅拌反应24h,分别得到加成度为5和4的氨基酸C60主产物,产率按加入的C60计算分别为30%,28%.氨基酸碳链的长度及加成产物在反应体系中能否及时沉淀析出影响和控制着加成度的大小.C60[NH(CH2)5COOH]5H5(3a),?C60(NHCH2CH2SO3H)4H4(6a)用柱层析进一步纯化,其结构组成经元素分析,1HNMR,13CNMR,IR所证实.6a的水溶性受溶液pH的影响较小,3a在不同pH缓冲溶液中的溶解性用光谱法测定,分别为:pH=10.25时为71.81mg?mL-1,pH=7时为23.68mg?mL-1,pH=3.36时为10.12mg?mL-1.在波长273nm处,3a的摩尔消光系数为ε=3.43×104L?mol-1?cm-1.

Preparation of water soluble fullerenes (C-60) derivatives is meaningful to biological study of fullerenes. Amination reaction of amino-acid with C-60 led to water soluble amino-acid C-60 derivatives. Reaction of C-60 with excess of NH2(CH2)(5)COO-Na+ (1) or NH2(CH2)(2)SO3-Na+ (4) (molar ratio is 1 : 10) at 80° C for 24 h afforded main amino-acid C-60 adducts with addition degree of 5 and 4, respectively. The yields based on the C-60 added were 30% and 28%, respectively. The addition degree was influenced by the length of hydrocarbon chain of amino-acid and precipitation of C-60 adducts from the reactant. CrO[NH(CH2)(5)COOH](5)H-5 (3a) and C-60(NHCH2CH2SO3H)(4)H-4 (6a) were further purified by silica column chromatography and characterized by H-1 NMR, C-13 NMR, IR, FAB-MS spectra and elemental analysis. The solubility of 6a was less pH dependent. The solubility of 3a in water at different pH was measured by the spectrophotometric method, exhibiting solubility of 71.81 mg . mL(-1) (pH=10.25), 23.68 mg . mL(-1) (pH=7) and 10.12 mg . mL(-1) (pH=3.36). The c value of 3a at 272.8 nm was 3.43 X 10(4) L . mol(-1) . cm(-1).