cobalt(3+);[(2R,3S,4R)-5-(5,6-dimethylbenzimidazol-1-yl)-4-hydroxy-2-(hydroxymethyl)oxolan-3-yl] [(2R)-1-[3-[(1R,2R,3R,7S,12S,13S,17S,18S,19R)-2,13,18-tris(2-amino-2-oxoethyl)-7,12,17-tris(3-amino-3-oxopropyl)-3,5,8,8,13,15,18,19-octamethyl-2,7,12,17-tetrahydro-1H-corrin-21-id-3-yl]propanoylamino]propan-2-yl] phosphate;cyanide

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 四吡咯及其衍生物
• 英文名称: cobalt(3+);[(2R,3S,4R)-5-(5,6-dimethylbenzimidazol-1-yl)-4-hydroxy-2-(hydroxymethyl)oxolan-3-yl] [(2R)-1-[3-[(1R,2R,3R,7S,12S,13S,17S,18S,19R)-2,13,18-tris(2-amino-2-oxoethyl)-7,12,17-tris(3-amino-3-oxopropyl)-3,5,8,8,13,15,18,19-octamethyl-2,7,12,17-tetrahydro-1H-corrin-21-id-3-yl]propanoylamino]propan-2-yl] phosphate;cyanide
• 化学式: C63H88CoN14O14P
• 分子量: 1355.4
• InChiKey: FDJOLVPMNUYSCM-QJRSUKKJSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  3.41
• 重原子数：
  93
• 可旋转键数：
  26
• 环数：
  8.0
• sp3杂化的碳原子比例：
  0.62
• 拓扑面积：
  476
• 氢给体数：
  9
• 氢受体数：
  21

ADMET

代谢

维生素B12被认为在肝脏转化为辅酶形式，并且可能以这种形式储存在组织中。

Vitamin B12 is believed to be converted to coenzyme form in the liver and is probably stored in tissues in this form.

来源:Hazardous Substances Data Bank (HSDB)

代谢

细胞内维生素B12以两种活性辅酶形式存在，分别是甲钴胺和脱氧腺苷钴胺。

Intracellular vitamin B12 is maintained as two active coenzymes methylcobalamin and deoxyadenasylcobalamin.

来源:Hazardous Substances Data Bank (HSDB)

代谢

维生素B12被认为在肝脏转化为辅酶形式，并且可能以这种形式储存在组织中。

Vitamin B12 is believed to be converted to coenzyme form in the liver and is probably stored in tissues in this form.

来源:Hazardous Substances Data Bank (HSDB)

代谢

细胞内的维生素B12以两种活性辅酶形式存在，分别是甲钴胺和脱氧腺苷钴胺。

Intracellular vitamin B12 is maintained as two active coenzymes methylcobalamin and deoxyadenasylcobalamin.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 相互作用

维生素B12从胃肠道吸收可能会被氨基糖苷类抗生素、秋水仙碱、缓释钾制剂、氨水杨酸及其盐类、抗惊厥药（例如，苯妥英、苯巴比妥、普里马多）以及钴对小肠的辐射和超过两周的过量饮酒降低。

ABSORPTION OF VITAMINE B12 FROM THE GI TRACT MAY BE DECR BY AMINOGLYCOSIDE ANTIBIOTICS, COLCHICINE, EXTENTED-RELEASE POTASSIUM PREPN, AMINOSALICYLIC ACID & ITS SALTS, ANTICONVULSANTS (EG, PHENYTOIN, PHENOBARBITAL, PRIMADONE), COBALT IRRADIATION OF THE SMALL BOWEL, & BY EXCESSIVE ALCOHOL INTAKE LASTING LONGER THAN 2 WK.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 相互作用

口服新霉素会显著降低维生素B12的胃肠道吸收。使用秋水仙碱似乎会增加新霉素引起的维生素B12吸收不良。

The gastrointestinal absorption of vitamin B12 can be considerably decreased by oral neomycin. Colchicine administration appears to increase neomycin-induced malabsorption of vitamin B12.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 相互作用

氨水杨酸诱导的维生素B12吸收减少可能是由于一些接受氨水杨酸（PAS）治疗的患者出现的轻度吸收不良综合征。

The decreased vitamin B12 absorption induced by aminosalicylic acid may be due to the mild malabsorption syndrome that occurs in some patients treated with aminosalicylic acid (PAS).

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 相互作用

患有恶性贫血的病人如果同时使用氯霉素，对维生素B12治疗的反应会很差。

Patients with pernicious anemia ... respond poorly to vitamin B12 therapy if chloroamphenicol is given concomitantly.

来源:Hazardous Substances Data Bank (HSDB)

毒理性

• 人类毒性摘录

维生素B12通常即使在大量服用时也没有毒性；然而，报告称会有轻微的暂时性腹泻、周围血管血栓形成、瘙痒、暂时性皮疹、荨麻疹、全身肿胀感、过敏性反应甚至死亡。尽管对维生素B12的过敏反应通常归因于制剂中的杂质，但少数患者对纯化的氰钴胺进行了皮肤测试反应呈阳性……。

Vitamin B12 is usually nontoxic even in large doses; however, mild transient diarrhea, peripheral vascular thrombosis, itching, transitory exanthema, urticaria, feeling of swelling of the entire body, anaphylaxis, and death have been reported. Although allergic reactions to vitamin B12 have generally been attributed to impurities in the preparation, a few patients have reacted positively to skin testing with purified cyanocobalamin ... .

来源:Hazardous Substances Data Bank (HSDB)

吸收、分配和排泄

在给小鼠静脉注射维生素B12的实验中，维生素B12迅速在胎盘积聚，并且缓慢转移到胎儿。给药后24小时，胎儿内的维生素B12浓度达到峰值，而且胎儿的积聚量与剂量有关。

IN MICE INJECTED IV WITH VITAMIN B12, THE VITAMIN ACCUMULATED RAPIDLY IN THE PLACENTA & WAS TRANSFERRED SLOWLY TO THE FETUSES. PEAK CONCN IN THE FETUSES WAS REACHED 24 HR AFTER DOSING, & FETAL ACCUMULATION WAS DOSE-DEPENDENT.

来源:Hazardous Substances Data Bank (HSDB)

吸收、分配和排泄

在/小鼠/中，维生素B12展现了不寻常的胎盘传递模式，即使母亲剂量为0.20微克，胎儿浓度平均还是比母亲高出130倍。这强烈表明存在特定的维生素B12转运机制，可能类似于它在胃肠道的吸收...

IN /MICE/ VITAMIN B12 PRESENTS UNUSUAL PATTERN OF PLACENTAL TRANSFER, FOR EVEN WITH 0.20 UG MATERNAL DOSE AVG FETAL CONCN IS 130 TIMES HIGHER THAN MATERNAL ONE. THIS INDICATES STRONGLY OPERATION OF SPECIFIC TRANSPORT MECHANISM FOR VITAMIN B12, POSSIBLY SIMILAR TO ITS GI ABSORPTION ...

来源:Hazardous Substances Data Bank (HSDB)

吸收、分配和排泄

在大鼠中，已经证明孕期维生素B12的胎盘传递增加。尽管每天传输的量与胎儿体重成比例，但从第10天到第19天，每克胎盘传输的量增加了十倍。

IN RATS, PLACENTAL TRANSFER OF VITAMIN B12 WAS SHOWN TO INCR DURING GESTATION. ALTHOUGH QUANTITY TRANSPORTED EACH DAY WAS PROPORTIONAL TO FETAL WT, THE AMT TRANSPORTED PER G OF PLACENTA INCR TEN-FOLD FROM DAY 10 TO DAY 19.

来源:Hazardous Substances Data Bank (HSDB)

吸收、分配和排泄

维生素B12在口服给药后，从远端小肠不规则吸收。饮食中的维生素B12与蛋白质结合，这种结合必须通过蛋白水解和胃酸分解才能被吸收。在胃中，游离的维生素B12与内因子结合；内因子是一种由胃粘膜分泌的糖蛋白，对于从胃肠道主动吸收维生素是必要的。维生素B12-内因子复合物进入肠道，在维生素B12部分被吸收进入系统循环之前，大部分复合物在回肠下段的特定受体位点暂时保留。

Vitamin B12 is irregularly absorbed from the distal small intestine following oral administration. Dietary vitamin B12 is protein bound and this bond must be split by proteolysis and gastric acid before absorption. In the stomach, free vitamin B12 is attached to intrinsic factor; intrinsic factor a glycoprotein secreted by the gastric mucosa, is necessary for active absorption of the vitamin from the GI tract. The vitamin B12-intrinsic factor complex passes into the intestine, where much of the complex is transiently retained at specific receptor sites in the wall of the lower ileum before the vitamin B12 portion is absorbed into systemic circulation.

来源:Hazardous Substances Data Bank (HSDB)

吸收、分配和排泄

在给小鼠静脉注射维生素B12的实验中，维生素B12迅速在胎盘积聚，并且缓慢转移到胎儿。胎儿体内的维生素B12浓度在给药后24小时达到峰值，而且胎儿的积聚量与剂量有关。

IN MICE INJECTED IV WITH VITAMIN B12, THE VITAMIN ACCUMULATED RAPIDLY IN THE PLACENTA & WAS TRANSFERRED SLOWLY TO THE FETUSES. PEAK CONCN IN THE FETUSES WAS REACHED 24 HR AFTER DOSING, & FETAL ACCUMULATION WAS DOSE-DEPENDENT.

来源:Hazardous Substances Data Bank (HSDB)