Hydrazine, Methyl

Carpino et al. recently disclosed the synthesis of the fused pyrazolinone-piperidine dipeptide 56 with potent growth hormone secretagogue activity. The synthesis of the intermediate pyrazolone was accomplished by reacting the ketoester 54 with methyl hydrazine in refluxing ethanol. ... 

Similarly, methylhydrazone 417, formed in situ from ketone 416 and methyl-hydrazine, cyclized to give good yield of 418 (Scheme 65) (82KGS1113). 

COMPOUND NAME CHLORODIFLUOROMETHANE DICHLOROFLUOROMETHANE CHLOROFORM HYDROGEN CYANIDE DIBROMOMETHANE DICHLOROMETHANE FORMALDEHYDE FORMIC ACID METHYL BROMIDE METHYL CHLORIDE METHYL FLUORIDE METHYL IODIDE NITROMETHANE METHANE METHANOL METHYL MERCAPTAN METHYL AMINE METHYL HYDRAZINE METHYL SILANE... 

Reduction of the benzene ring is also compatible with activity in this group. Reaction of N-methyl-2-thiocarbamoylcyclohexanone (57) with methyl hydrazine... 

TABLE 3-8 Lethality (LC50) of Hydrazine and Methylated Hydrazines in Rodents... 

Jacobson, K.H., J.H.Clem, H.J.Wheelwright, Jr., W.E.Rinehart, and N.Mayes. 1955. The acute toxicity of the vapors of some methylated hydrazine derivatives. AMA Arch. Ind. Health 12 609-616. 

Keller, W.C., C.T.Olson, and K.C.Back. 1984. Teratogenic assessment of three methylated hydrazine derivatives in the rat. J. Toxicol. Environ. Health 13 125-131. Kinkead, E.R., C.C.Haun, E.H.Vemot, and J.D.MacEwen. 1985. A chronic inhalation toxicity study on monomethylhydrazine. AFAMRL-TR-85-025. Aerospace Medical Research Laboratory, Wright-Patterson AFB, OH. 

Keller, W.C., C.T.Olson, and K.C.Back. 1984. Teratogenic assessment of three methylated hydrazine derivatives in the rat. J. Toxicol. Environ. Health 13 125—131. 

The survey of hazards and safety procedures involved in handling rocket fuels and oxidisers includes liquid hydrogen, pentaborane, fluorine, chlorine trifluoride, ozone, dinitrogen tetraoxide, hydrazine, methyl hydrazine and 1,1-dimethyl hydrazine [1]. The later volume [2] is a bargain compendium of five NFPA publications ... 

Diazirines are the cyclic isomers of the alphatic diazo compounds. Both the diaziridines and the diazirines are starting materials for the synthesis of alkyl hydrazines. 3,3-Pentamethyl-enediaziridine can be hydrolyzed quantitatively to hydrazine. Methylamine may be substituted for ammonia in the procedure resulting in l-methyl-3,3-pentamethylenediaziridine (m.p. 35-36°, yield 62% of theoretical) and then methyl hydrazine. Use of ethylenediamine leads to ethylene bis-hydrazine via a bifunctional diaziridine (m.p. 143-144°, yield 48% of theoretical). Ammonia can also be replaced by w-propylamine or cydo-hexylamine cyclohexanone by acetone. 

The hydroxymethyl and carboxyl group of Ser can participate in pyrazole-ring formation, as shown in the transformation of A -protected L-Ser with the Mitsunobu reagent into a /3-lactone which afforded the N-protected serine hydrazide upon treatment with methyl hydrazine. Cyclization to 25 was achieved by diisopropyl azodicarboxylate (DIAD) and TPP [90H(31)79]. 

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