Валиномицин

Химические свойства

white crystalline powder

Использование

Valinomycin is a hydrophobic cyclodepsipeptide with potent antitumour activity. Valinomycin is a highly selective potassium ionophore and this action leads to a diverse range of profound cell membrane effects. More recently, valinomycin has found application as a biosensor to detect to detect potassium efflux.

Определение

ChEBI: Valinomycin is a twelve-membered cyclodepsipeptide composed of three repeating D-alpha-hydroxyisovaleryl-D-valyl-L-lactoyl-L-valyl units joined in sequence. An antibiotic found in several Streptomyces strains. It has a role as an antiviral agent, an antimicrobial agent, a potassium ionophore and a bacterial metabolite. It is a cyclodepsipeptide and a macrocycle.

Общее описание

Shiny crystalline solid. Used as an insecticide and nematocide. Not registered as a pesticide in the U.S.

Профиль реактивности

VALINOMYCIN is an amide. Amides/imides react with azo and diazo compounds to generate toxic gases. Flammable gases are formed by the reaction of organic amides/imides with strong reducing agents. Amides are very weak bases (weaker than water). Imides are less basic yet and in fact react with strong bases to form salts. That is, they can react as acids. Mixing amides with dehydrating agents such as P2O5 or SOCl2 generates the corresponding nitrile. The combustion of these compounds generates mixed oxides of nitrogen (NOx).

Угроза здоровью

VALINOMYCIN is highly toxic orally.

Пожароопасность

When heated to decomposition, VALINOMYCIN emits toxic fumes of nitrogen oxides.

Биологическая активность

Selective K + ionophore (K 0.5 values are 48, 73, 75, 93 and 246 mM for K + , Rb + , Cs + , Na + and Li + respectively) that transports K + across biological and artificial lipid membranes. Inhibits Ca 2+ -ATPase activity and induces apoptosis through mitochondrial membrane depolarization, caspase-3 activation and phosphatidylserine translocation in vitro .

Методы очистки

Recrystallise valinomycin from dibutyl ether or Et2O. It is dimorphic: modification A crystallises from n-octane, and modification B crystallises from EtOH/H2O. It is soluble in pet ether, CHCl3, AcOH, BuOAc and Me2CO. [Smith et al. J Am Chem Soc 97 7242 1975, UV, IR and NMR see Brocknmann & Schmidt-Kastner Chem Ber 88 57 1955, Beilstein 27 I 9728. 17 IV 9728.]