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G A Digenis

Publications and source records attributed to G A Digenis.

At least 91 records · Page 5Linked to original sources
PubMed1975

Preparation of [18-F]haloperidol.

A procedure is described that permits the preparation of [18F]haloperidol in 140 min at specific activities ranging from 4-5 muCi mg-1. A key step in the synthetic route involves the incorporation of 18F into the molecule through a Schiemann-type reaction, which involves the pyrolysis of the diazonium tetrafluoroborate salt of 4-[4-(p-chlorophenyl)-4-hydroxypiperidino]-4'-aminobutyrophenone.

Fluorine↗
PubMed1975

Preparation of nitroso-13N-labeled nitrosoureas.

A method is described for the preparation of 13N-labeled N-nitrosoureas, specifically 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea. The 13N is generated as ammonia by the 12C(d,n)13N reaction on methane gas. The product is selectively trapped and subsequently oxidized to nitrous acid which reacts with the parent urea in solution to form the 13N-labeled nitrosourea.

Isotope Labeling↗
PubMed1975

Methionine replacement value of N-acetylmethionine and homocysteinethiolactone hydrochloride for growing rats.

The ability of young growing rats to absorb DL-homocysteinethiolactone hydrochloride (HCTL-HCl) and N-acetyl-DL-methionine (NAM) and to use them for growth when fed a methionine-deficient diet was studied. In situ intestinal absorption studies demonstrated that both compounds are readily absorbed. Intestinal half-times were 24 minutes for NDTL-HCl and 44 minutes for NAM. Adding molar equivalents of 0.2 or 0.4% methionine to a 0.2% methionine basal diet fed ad libitum resulted in 28-day gains that were 83.2 and 91.1%, respectively, for NCTL-HCl and 94.6 and 99.8% for NAM of the average gain resulting when DL-methionine was added at equivalent levels. Feed efficiencies were also significantly (P smaller than 0.05) improved over rats fed the basal diet. Increasing the HCTL-HCl addition to 0.6% reduced feed intake and gain but not feed efficiency.

Acetates↗