Piperazine-2,6-diones reviews

Studies with tryptophan and tyrosine derivatives and with tryptophan- or tyrosine-containing dipeptides or piperazine-2,5-diones (diketopiperazines, DKP) revealed structural moieties that affect the fluorescence quantum yield of these aromatic amino acids (for a review, see... 

The objective of the present review is to discuss all aspects of the chemistry of piperazine-2,5-diones and their synthesis, physical chracter-istics, chemical reactivity and applications. Earlier reviews had focused on certain specific topics thus the review by Sammes (75FOR51) is mainly oriented toward natural products containing the piperazine-2,5-dione ring, whereas the one by Anteunis (78BSB627) deals exhaustively with conformational aspects of the ring, as well as those of the side chains. 

The methylene groups at positions 3 and 6 of piperazine-2,5-diones are known to undergo facile condensation with aldehydes to form the corresponding a,/3-unsaturated amides. Two earlier reviews have dealt with this subject. (75FOR51 80FOR251). The review by Sammes covers the literature to 1972 on the synthesis, stereochemistry, and reactivity of... 

Piperazine-2,5-diones and related lactim ethers are covered by S. Rajappa and M. V. Natekar of the National Chemical Laboratory, Pune, India. Their chapter represents the first comprehensive review of these highly important intermediates for the preparation of a wide variety of natural products. 

Examples of photorearrangement in nitrones and heteroaromatic N-oxides have again been described, and the subject has been critically reviewed. The hydroxyoxaziridines (81) have been prepared by irradiation of the corresponding 1-pyrroline 1-oxides (82), ° whereas photorearrangement of the dinitrone (83) gave the oxaziridines (84) and (85) and the lactam (86) oxaziridines (84), (85), and (86) were converted into the piperazine-2,5-dione (87) by further irradiation. ... 

A number of reviews of piperazinones, particularly piperazin-2,5-diones, has been published. These are listed in Table XI.1 and some references to other data are recorded below. 

The preparation and reactions of piperazine-2,S-diones has been much discussed in the reviews mentioned above and in papers by Sammes and co-workers (314, 314a, 1066-1068, 1078,1127,1128, 1616). 

Sterically pure piperazinediones have been prepared from formate salts of dipeptide methyl esters (1622). The conformation of piperazine-2,5-diones has been reviewed (1623). 

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