Reference

Fluorine-19 NMR studies on the mechanism of riboflavin synthase

Fluorine-19 NMR studies on the mechanism of riboflavin synthase. Synthesis of 6-(trifluoromethyl)-7-oxo-8-(D-ribityl)lumazine and 6-(trifluoromethyl)-7-methyl-8-(D-ribityl)lumazine. Cushman, Mark; Patel, Hemantkumar H. 381-88-4 which is the cas registry number of some chemical is mentioned.; Scheuring, Johannes; Bacher, Adelbert (Sch. Pharm. Pharm. Sci., Purdue Univ., West Lafayette, IN 47907, USA). J. Org. Chem., 57(21), 5630-43 (English) 1992. CODEN: JOCEAH. ISSN: 0022-3263. DOCUMENT TYPE: Journal CA Section: 33 (Carbohydrates) Section cross-reference(s): 7, 28 Title oxo-(D-ribityl)lumazine I was synthesized by reaction of Me trifluoropyruvate with 5-amino-6-(D-ribitylamino)pyrimidine-2,4(1H,3H)-dione hydrochloride and utilized as a 19F NMR probe of the light riboflavin synthase of Bacillus subtillis. I was found to be an inhibitor of riboflavin synthase with an inhibition const. KI = 55 mM. The enzyme-bound ligand gave rise to several broad 19F NMR signals which were shifted to low field. The bound ligand I could be displaced from the enzyme by the enzyme product, riboflavin (II), and the product analog, 5-nitroso-6-(ribitylamino)-2,4(1H,3H)-pyrimidinedione. Title methyl-(D-ribityl)lumazine III was synthesized by reaction of 5-amino-6-(D-ribitylamino)pyrimidine-2,4(1H,3H)-dione hydrochloride with 1,1,1-trifluorobutane-2,3-dione. Three mols. of III can be bound relatively tightly per mol of riboflavin synthase, i.e., one ligand mol. per protein subunit. A scheme for the catalytic cycle of riboflavin synthase is proposed. .

Fluorinated ketene dithioacetals

Fluorinated ketene dithioacetals. 1. Preparation and application to the synthesis of a-(trifluoromethyl)thiocarboxylic S-esters and aldehyde derivatives. Muzard, Murielle; Portella, Charles (Lab. Rearrang. Therm.Several reagents such as 381-88-4 is used here. Photochim., Fac. Sci., Reims F-51062, Fr.). Synthesis, (10), 965-8 (English) 1992. CODEN: SYNTBF. ISSN: 0039-7881.Several substances are used for example 381-88-4 which is its cas registry number. DOCUMENT TYPE: Journal CA Section: 21 (General Organic Chemistry) a-(Trifluoromethyl)ketene dithioacetals CF3CR:C(SR1)2 [R = Et, n-hexyl, cyclohexyl, Ph, R12 = (CH2)3; R = cyclohexyl, Ph, R1 = Ph] were synthesized by Peterson reaction from trifluoromethyl ketones CF3COR and trimethylsilyl dithioacetals Me3SiCH(SR1)2. Acid hydrolysis and redn. yielded a-(trifluoromethyl)thiocarboxylic S-esters CF3CHRC(O)SR2 [R2 = (CH2)3SH, Ph] and a-trifluoromethyl dithioacetals CF3CHRCH(SR1)2, resp. Transacetalization of the latter with ethanol gave the corresponding di-Et acetal. New procedures were developed to effect redn. and transacetalization. ..