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1. 1. Modifying Cooking Practices to Reduce the Formation of Heterocyclic Amines

   Författare :Elna Hallgard; Avdelningen för livsmedel och läkemedel; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Livsmedelsteknik; Food and drink technology; cancer; frying; mutagens; beefburger; chicken; heterocyclic amines; cooking;

   Sammanfattning : Commonly cooked meat dishes contain heterocyclic amines (HAs) at ng/g levels. HAs are animal carcinogens, form DNA adducts in human tissues, and have been associated with increased risk of cancer in epidemiological studies, and it is thus recommended that human intake be decreased. LÄS MER

3. 2. New methods for the synthesis of N-heteroaromatics and imines

   Författare :Kenji Kopf; Belén Martín Matute; Joseph P. A. Harrity; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; heterocyclic; heteroaromatic; atropisomer; pyridine; pyrimidine; MOF; amine coupling; catalysis; benzannulation; organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis is divided in four chapters, containing the work realised in two universities and has as the aim the synthesis of nitrogen-containing compounds. The first chapter describes the project realised at The University of Sheffield. LÄS MER

4. 3. Dietary heterocyclic amines and human cancer risk

   Författare :Katarina Augustsson; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :cancer; colon; rectum; bladder; kidney; human; heterocyclic amines; meat;

   Sammanfattning : Heterocyclic amines formed in meat during cooking are multi-site animal carcinogens and form DNA adducts in human tissues, but their relevance to human carcinogenesis has yet to be determined. The aim of this thesis was to investigate, by epidemiological methods, whether heterocyclic amines are responsible for part of the diet-related cancer burden in humans. LÄS MER

5. 4. Synthetic studies of heterocyclic natural products

   Författare :Jeffrey J Mason; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :Heterocycles; alkaloids; natural products; luotonin A; cephalandole A; cephalandole B; benzoxazinone; tryptanthrin; ophiuroidine; pyrroloquinazolinone; isatin; Prey demethylation; pyridinium hydrochloride; demethylation; microwave synthesis;

   Sammanfattning : The methods that were developed for the synthesis of the heterocyclic natural products luotonin A, ophiuroidine, cephalandole B, and the indol-3-yl-benzoxazinones of cephalandole A are described in this thesis. The reoccurrence of the 4(3H)-quinazolinone structure is a common theme throughout these studies, and an overview of some quinazoline chemistry is introduced in the first chapter. LÄS MER

7. 5. Aerobic Oxidative N-Heterocyclic Carbene Catalysis via Multistep Electron Transfer - Method Development and Applications

   Författare :Anton Axelsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; N-heterocyclic carbene; asymmetric synthesis; esterification; glycerol; electron transfer mediator; green chemistry; telescoped reaction; Organocatalysis; aerobic oxidation; dihydropyranone;

   Sammanfattning : Oxidation reactions are ubiquitous in synthetic chemistry, but generally suffer from formation of large amounts of potentially toxic byproducts. Aerial oxygen represents an ideal oxidant since it is inexpensive, non-toxic and only forms water as a byproduct. LÄS MER