Methylation agents, list

Exercise 17-29 If you wished to prepare the methyl ether of 4-hydroxy-3-penten-2-one by O-alkylation, what base and which of the methylating agents listed would you... 

A high level of homocysteine is an indication of a low rate of conversion of homocysteine to methionine and hence a low level of the methylating agent S-adenosyl methionine. The latter, plus the toxic effects of homocysteine, provides a link between the reactions listed above and three diseases cardiovascular disease (Chapter 22), senile dementia (Chapter 14) and cancer (Chapter 21). 

Chloromethyl methyl ether and bis-chloromethyl ether (CICH2 OCH2Cl) in common with several alkylating agents possess carcinogenic properties in experimental animals and have been listed as assumed human carcinogens similar hazardous properties associated with dichloromethyl methyl ether have not been reported but it would be prudent to handle this compound with due care. 

Table 2 illustrates that the majority of Schedule numbers allow deriving only one or a few different possible chemicals. One Schedule number however, Schedule 2.B.4, describes millions of possibilities ( Chemicals, except for those listed in Schedule 1, containing a phosphorous atom to which is bonded one methyl, ethyl or propyl (normal or iso) group but no further carbon atoms ) and more importantly, the theoretical possibilities for the nerve agents... 

Table 10.1 lists approximate transfer constants of some common agents in polymerization of styrene, methyl methacrylate, and vinyl acetate. 

Compounds are listed proximately in order of descending toxicity. "Highly toxic" N-methyl carbamates have hsted oral LD50 values (rat) less dian 50 mg/kg body weight "moderately toxic" agents have LD50 values in excess of 50 mg/kg. 

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