6-Methoxy-4-methyl-2-pyrone

Keywords 4-methoxy-6-methyl-2-pyrone, maleinimide, [2+2]photocycload-dition, cyclobutane... 

CpFe(CO)2(pyrone)]+, pyrone = 4-methoxy-6-methyl-2-pyrone and 3-bromo-4-methoxy-6-methyl-2-pyrone were examined as potential CO releasing molecules but failed to release [195]. 

Two compounds, [CpMo(CO)3(pyrone)]+, pyrone = 4-methoxy-6-methyl-2-pyrone, 42, and 3-bromo-4-methoxy-6-methyl-2-pyrone, 43, were examined as potential CO releasing molecules. Both release CO to myoglobin. [CpMo(CO)3(3-bromo-4-meth-oxy-6-methyl-2-pyrone)]+, 43, which showed the faster CO release also showed good cell viability, cytotoxicity and inhibition of nitrite production using murine... 

Irradiation of cocrystals between 4-methoxy-6-methyl-2-pyrone and malei-mide gave an endo-5,6-[2-l-2] adduct (Scheme 19) [46]. Sensitized solution photolysis furnished a 1 2 adduct as a major product. 

Pyrenochaeta terrestris, the causal agent of the onion pink root disease, induces a proliferation of host membrane prior to cellular disruption several cell layers in advance of the infection front (1). The pathogen produces a phytotoxin known as pyrenocine A (5- crotonyl-4-methoxy-6-methyl-2 pyrone) (2). We believe that pyrenocine A may be involved in this response and report some observations on the effects of pyrenocine A on limited aspects of plant lipid metabolism. 

Methoxy-6-methyl-4-pyrone heated 5 min. at 140° in the presence of 2,4-di-methoxy-6-methylpyrylium fluoroborate in a sealed tube -> 4-methoxy-6-methyl-2-pyrone. Y ca. 93%. P. Beak, Tetrah. Let. 1963, 863. 

Irradiation of the 1 1 complex crystals of 4-methoxy-6-methyl-2-pyrone 35 and maleimide 36 gives 37 in 54% yield as a sole product, which is entirely different from the solution products 39 and 40. The peri-, site-, and stereospecific photoreaction in the solid state is considered to be brought about by two sets of the hydrogen bonding and CT stacking between 35 and 36 in the complex. 

Obata, X, Shimo, T., Yoshimoto, S., Somekawa, K., and Kawaminami, M., Peri-, site- and stereo-controUed photocycloaddition of 4-methoxy-6-methyl-2-pyrone with maleimide induced by the hydrogen bond and CT stacking in the sohd state, Chem. Lett., 181—182,1999. 

Shimo, X, Somekawa, K., Wakikawa, Y, Uemura, H., Xsuge, O., Imada, K. and Xanabe, K., Photoadducts of 4,6-dimethyl- and 4-methoxy-6-methyl-2-pyrones with chloroethylenes and their dehydrochlorination, 5m//. Chem. Soc. Jpn., 60, 621, 1987. 

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