A simple and efficient synthesis of norbixin and crocetin diesters is described following the schemes C2 + C2o + C2,=C24 and C3 + C14 + C3 = C20 respectively. By means of the Wittig reaction crocetin di‐aldehyde is condensed with a bromoacetic acid ester and a C14‐dialdehyde with an α‐bromopropionic acid ester. The intermediate tri‐ phenylphosphorane compounds are crystalline and easily isolated in a pure state.

The industrial β‐carotene manufacturing procedure based on Inhoffen's synthesis C19 + C2 + C19 = C40 is described. β‐Ionone is first lengthened to β‐C14‐aldehyde as in our vitamin A‐synthesis. By acetalisation, condensation with vinyl ether and treatment with acid the new β‐C16‐aldehyde is obtained. Repetition of the same reactions with propenyl ether leads to the β‐C19‐aldehyde. For the final steps simple methods were developed giving high yields. All the chemical, physical and biological constants of synthetic β‐carotene are identical with those of the natural compound. Exact data on light absorption are given. Extensive experiments with the synthetic β‐carotene on rats and rabbits show that even very large doses have no toxic effects.

A simple and efficient synthesis of lycopene is described based on stepwise lengthening of a symmetrical C10‐dialdehyde as central component. This C10‐dialdehyde is lengthened at both ends, first with vinyl ether and then with propenyl ether, leading to a C20‐dialdehyde which is transformed into crocetin dialdehyde by partial hydrogenation of the central triple bond. By means of a new reaction devised by Wittig, crocetin dialdehyde is condensed at both ends with geranylidene‐triphenylphosphorane and lycopene is obtained according to the scheme C10 + C20 + C10 = C40. This synthetic pigment is identical with pure natural lycopene isolated from tomato juice. The Wittig reaction also allows a new β‐carotene synthesis using the components cyclogeranylidene‐triphenylphosphorane and 8,8′‐dehydro‐crocetin dialdehyde.

The mixed anhydride from factor V,, and ethyl hydrogen carbonate reacts with nL-2-amino-1-methylethyl sodium hydrogen phosphate to give the phosphoric acid monoester of factor B (containing racemic 1-amino-2-propanol). Compounds of this type are believed to be intermediates in the biosynthesis of cobalamines.Vitamin B,, kann synthetisch aus Faktor V,,, dessen Struktur als die des Cobyrinshre-abcdeg-hexamids 3, bewiesen wurde 4), gewonnen werden. Das verwendete Syntheseschema erlaubt auch den Aufbau neuartiger, unnatiirlicher Analoga des Vitamins B,,, in denen D-1-.4mino-2-propanol durch andere Aminoalkohole ersctzt ist. Die SchluWstufe besteht in der Kondensation von I mit I1 a oder Analoga desselben.Die Herstellung des als Ausgangsmaterial benotigten gemischten Anhydrids I aus Faktor V,, und Kohlensaure-monoathylcster ist in einer vorangehenden Mitteilung beschrieben worden 4). (1-a-~-Ribofuranosy~-5,6-dimethyl-benzimidazol)-3'-dihydrogenphosphorsaureester (III), der im folgenden als a-Ribazolphosphat bezeichnet wird, kann sowohl synthetisch als auch durch Abbau von Vitamin B,, liergestellt werden 5 ) ) " ) ' ) . Beim Behandeln des a-Ribazolphosphats in einem Gemisch von Formamid, tert .-Butan01 und Ammoniak mit Dicyclohexyl-carbodiimid entsteht in praktisch quantitativer Ausbeute das cyclische Phosphat IV [(l-a-~-~ibofuranosyl-5,6-dimcl) Biochemisches Forschungslaboratorium der ASCHAFFENBURGER ZELLSTOFFWERKE AG.,

The synthesis of tenoxicam, 4-hydroxy-2-methyl-N-2-pyridyl-2H-thieno[2,3-e]-1,2-thiazine-3-carboxami de 1,1-dioxide (1e), and of the analogues with various residues on the ring nitrogen and the amide nitrogen is described. This new class of "oxicams" has pronounced antiinflammatory and analgesic properties. The very specific structure-activity relationship of isomeric and isosteric groups at the amide nitrogen has been evaluated. The substituent in position 2 also has a great influence on the pharmacological properties. Tenoxicam is presently undergoing clinical trials.