With aziridines

SULFURIZATIONAND SULFURCm ORINATION] (Vol23) -reaction with aziridine [IMINES, CYCLIC] (Vol 14)... 

The reaction of hydrogen sulfide with aziridines in the presence of aldehydes or ketones provides a simple route to two-substituted thiazohdines (2,114-116). 

The reaction of aliphatic and aromatic mercaptans with aziridines yields thioethers (117—119). 

Acidic deacetylation of 129 followed by alkaline treatment of the intermediate 130 provided denitrocyclization product 131 in 51% overall yield (77KGS1271). A similar cyclized product was reported to be formed from 2-nitrobenzimidazole (132), which when treated with aziridine, instead of the corresponding aminoethyl derivative, provided 93% of benzimidazo[2,l-fo]imidazole 133 (Scheme 21) (82JMC1342). 

Cancer chemothCTapeutic agents as a rule poorly penetrate the blood brain barrier. Brain tumors are thus not readily treatable by chemotherapy. Diaziquone (at one time known as AZQ) is an exception to this generalization. Treatment of chloranil (213) with the anion from urethane gives intermediate 214, probably by an addition elimination scheme. Displacement of the remaining halogen with aziridine yields diaziquone (215) [.55J. 

The action of nitrous acid on the benzodiazepine A -oxide 38 gives the nitrosoamino derivative 39,234 which reacts with alcohols, ethanethiol and various amino compounds, such as hydrazines and guanidine, by replacement of the methyl(nitroso)amino group.235 Reaction with aziridine affords the aziridinyl compound 40f or the 2-(aziridin-l-yl)ethylainino derivative 40g, depending on the conditions. 

Kinetic resolution of the racemic aziridine-2-carboxylate 82 (Scheme 3.26) was reported by Iqbal and co-workers [74], When 82 was allowed to react with N-cinna-moyl-L-proline (81) under mixed anhydride coupling conditions, the N-acyl azir-idine 83 was obtained in optically pure form along with aziridine 84. 

Carbanions of active methylene compounds also react with aziridine-2-car-boxylic esters to give ring-opened products [129]. The ring-opened intermediates usually cyclize spontaneously to pyrrolidones. Treatment of 190 (Scheme 3.70) with the sodium enolate of dimethyl malonate 191, for example, afforded pyrroli-done 192 in 15% isolated yield, together with 30% of the debenzoylated product 193. 

It is likely that the madurastatins are biosynthesized on a nonribosomal peptide synthetase, from salicylic acid as the starter acid. L-Serine is probably the precursor to the aziridine moiety, with epimerization occurring on the enzyme-bound amino acid as found for other nonribosomal peptides, with aziridine formation occurring at a late stage. Compounds 120 and 123 could therefore be biosynthetic precursors to 119 and 122, respectively. 

Reaction of organometallic compounds with aziridines 10-103 Reaction of organometallics with aziridines... 

Reacation of amines with aziridines Diamination (additon of nitrogen, nitrogen) Dimerizatino of imines... 

The majority of reactions of aziridines deal with acid-catalyzed ring opening with various nucleophiles. In this review only reactions with aziridine-2-car-boxylic esters are summarized (for other types of aziridines, see ref. [3]). 

Similarly, another accident occurred when metallic silver came into contact with aziridine. According to the authors of the report, the accident was interpreted by the formation of an aziridine silver derivative. Comparing this behaviour with the one of ethylene oxide when silver is present, a danger which is of the same nature is demonstrated. The interpretation that had been given at the time was based on the presence of acetylene in ethylene oxide, whose silver derivatives are very sensitive explosives. It may be that acetylene traces were present in aziridine although none of the authors mentioned such as possibility as far as we know. 

With aziridine, nitrogen pentoxide forms a compound that is very unstable and is thought to have the following structure ... 

Partially hydrolyzed acrylics crosslinked with aziridine prepolymer or carbodiimide ... 

Scheme 1.44 Test reaction with aziridine sulfide ligands.

Reactions with aziridine were also described.[38]... 

Another problem with the reaction of phenols with aziridines is the selectivity between O-alkylation vs C-alkylation. A recent report has identified that the use of (ArO)3B selects for C-alkylation <06OL2627>. Most of the examples reported in this paper showed less than 5% of the O-alkylation product. What is interesting about this report is the stereochemistry of the product. While the mechanism is not known, the product is formally an SNl type product. Generally less than 5% was the product of inversion of configuration (the Sn2 product). In addition to the A-tosyl, both the A-Cbz and A-Dpp aziridines gave excellent yields of aziridine-opened product. 

Aziridinylbenzaldoxime 340, formed from the reaction of a hydroximoyl chloride with aziridine 339 (Scheme 56), reacts with HG1 to form the chloroalkyl-substituted amidoxime 341. Reaction with sodium hydride affects ring closure to give the 3-aryl-4,5-dihydro-5-isopropyl-l,2,4-oxadiazoles 343. This latter reaction is proposed to proceed... 

Stamm, H. and Gerster, G., Reactions with aziridines. XXI. The (Michaelis-) Arbuzov reaction with N-acyl aziridines and other amidoethylations at phosphorus, Tetrahedron Lett., 1623, 1980. 

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