Acrylic acid Dimethyl sulfide

Yang H, McTaggart AR, Davidson AT, Burton H (1994) Measurement of acrylic acid and dimethyl sulfide in Antarctic coastal water during a summer bloom of Phae-ocystis pouchetii. the NIPR Symposium on Polar Biology, no. 7. National Institute of Polar Research, Tokyo, pp 43-52... 

Some of the volatile odorous components of algae, such as dimethyl sulfide, are unpleasant and are mainly distributed in Chlorophyta and also in some Rhodophyta [112]. Dimethyl sulfide and acrylic acid have resulted from the enzymatic cleavage products of dimethyl-jS-propiothetin (dimethyl-2-carboxyethylsulfonium hydroxide), from Enteromorpha intestinalis and Acrosiphonia centralis [113], which is a metabolite of methionine [45] released into the sea water [112]. 

Dimethylpropiothetin occurs in certain marine algae. An enzyme has been obtained from one of these that eliminates dimethyl sulfide from the thetin, leaving acrylic acid. ... 

Compound Name Methyl Acetate Propionic Acid Propionic Anhydride Methyl Mercaptan Dimethyl Sulfide Formic Acid Methyl Alcohol Hexamethylenetetramine Methoxychlor Methoxychlor Diethylebe Glycol Monomethyl Ether Methylacetylene-Propadiene Mixture Methylacetylene-Propadiene Mixture Crotonaldehyde Methyl Acrylate Methyl Formal Methyl Alcohol Methallyl Chloride Methylamine N-Methylaniline Methyl Amyl Acetate Methyl Amyl Alcohol Methyl Isobutyl Carbinol N-Amyl Methyl Ketone O-Toluidine 0-Toluidine N-Methylaniline N-Methylaniline Propyleneiniiine. 

Various alkylating agents are used for the preparation of pyridazinyl alkyl sulfides. Methyl and ethyl iodides, dimethyl and diethyl sulfate, a-halo acids and esters, /3-halo acids and their derivatives, a-halo ketones, benzyl halides and substituted benzyl halides and other alkyl and heteroarylmethyl halides are most commonly used for this purpose. Another method is the addition of pyridazinethiones and pyridazinethiols to unsaturated compounds, such as 2,3(4//)-dihydropyran or 2,3(4//)-dihydrothiopyran, and to compounds with activated double bonds, such as acrylonitrile, acrylates and quinones. 

The benzo derivative (128) reacts as a thiocarbonyl ylide. Addition of N-(p-tolyl)maleimide gives a mixture of the exo (71%) and endo (16%) adducts (129 Ar=p-tolyl), which in hot acetic acid eliminate hydrogen sulfide giving the pyrido[l,2-a]benzimidazole (130 Ar=p-tolyl). Analogous 1 1 cycloadducts (131) are formed with dimethyl maleate, dimethyl fumarate, methyl crotonate and methyl acrylate. In contrast to the transformation (129) —> (130), treatment of the adducts (131 R = H, Me) with hot acetic acid gives the tetracyclic compounds (133) via the benzimidazole derivatives (132 R = H, Me). Reaction with alkynic 1,3-dipolarophiles gives pyrido[l,2-a]benzimidazole (134) by desulfurization of the primary adducts (80CL1369). 

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