Spermidine

These compounds are present in almost all mam malian cells where they are believed to be involved in cell differentiation and proliferation Because each ni trogen of a polyamine is protonated at physiological pH (7 4) putrescine spermidine and spermine exist as cations with a charge of + 2 +3 and + 4 respectively... 

Spermidine trihydrochloride [334-50-9] M 245.3, m --250°(dec), 256-258", for pKa see free base above. Recrystd from dry 3% HCl in ethanol adding dry Et20 if necessary. Filter rapidly and dry in a vac desiccator. Alternatively centrifuge the crystals off wash them with dry Et20 and dry in a vacuum. 

Spermine 4HC1 (7V,7V-bis(3-aminopropyl)-l,4-butanediamine 4HC1) [306-67-2] M 348.2, m 313-315". The pKs are similar to spermidine above. Purification as for spermidine trihydrochloride above. 

Polyamine (Section 22.4) A compound that contains many amino groups. The term is usually applied to a group of naturally occurring substances, including spermine, spermidine, and putrescine, that are believed to be involved in cell differentiation and proliferation. 

Ac2NOMe selectively acylates a primary amine of a spermidine. ... 

In addition, the linear, biogenic polyamines, spermidine and spermine, originally isolated from human sperm19), have been long known. Their structures are shown below. 

The conditional association constant for [18]aneN4 ( cyclic spermine ) with ATP - at pH 7.5 is calculated from the (3L value (Table 5) and protonation constants (Table 1) to be 2.4x 105 M-1, which is larger than the association constants for the linear spermidine (9 xi 02 M ) and spermine (9.5 x 103 M-1)23). It is also of interest that cyclic spermine is selective for ATP over AMP (ratio association constants is 700), while linear spermine prefers ATP to AMP only by a ratio of 26 to 1 43). The selective complexation of biologically important anions is of particular interest, especially if the ligands are converted into selective anion carriers by attachment of lipophilic hydrocarbon chains. 

Eflornithine (difluoromethylornithine, DFMO) inhibits the ornithine decarboxylase of the polyamine pathway, in both the trypanosome and the mammalian cell, by acting as an irreversible competitor of the natural substrate ornithine. Inhibition of ornithine decarboxylase results in depletion of the polyamines, putrescine, spermidine and spermine, which are essential for cell proliferation. Eflornithine selectively harms the parasite and not the mammalian cells, despite acting as an ornithine decarboxylase inhibitor in both cell types. This selectivity is explained by the lower rate of ornithine decarboxylase production in the parasite, as compared to mammalian cells. Due to the high turnover rate, mammalian cells are capable of quickly replenishing inhibited ornithine decarboxylase by newly... 

Spermidine is one of the most common natural polyamines with the following structure NH2(CH2)3 NH(CH2)4NH2. 

CSH8O3 148-53-8) see Alibendol Befunolol Nipradilol (-)-3-bydroxy-3-metboxycarbonyl-l,2-didebydroaspido-spermidine-9-oxide... 

---