4,4 ,4"- iris methyl

RS- P-Aminoisobutyric acid (a-methyl-P-alanine) [10569-72-9] M 103.1, m 176-178 , 178-180 , 181-182 , R -(-)- isomer [144-90-1] m 183 , [a] -21 (c 0.43, HjO), pKes,(,) 3.7, pKEst(2) 10.2. Colorless prisms from hot H O, were powdered and dried in vacuo. The purity is checked by paper chromatography (Whatman 1) using ninhydrin spray to visualise the amino acid Rp values in 95% MeOH and n-PrOH/5N HCOOH (8 2) are 0.36 and 0.50 respectively. [Kupiecki and Coon Biochem Prep 7 20 7960 Pollack J Am Chem Soc 65 1335 7943.] The R-enantiomer, isolated from iris bulbs or human urine was crystd from H2O and sublimed in vacuo [Asen et al. J Biol Chem 234 343 7959]. The RS-hydrochloride was recrystd from EtOH/Et20 m 128-129 , 130° [Bbhme et al. Chem Ber92 1258, 1260, 1261 7959]. 

These formulae explain the scission products of the two alkaloids and the conversion of evodiamine into rutaecarpine, and were accepted by Asahina. A partial synthesis of rutaecarpine was effected by Asahina, Irie and Ohta, who prepared the o-nitrobenzoyl derivative of 3-)3-amino-ethylindole-2-carboxylic acid, and reduced this to the corresponding amine (partial formula I), which on warming with phosphorus oxychloride in carbon tetrachloride solution furnished rutaecarpine. This synthesis was completed in 1928 by the same authors by the preparation of 3-)S-amino-ethylindole-2-carboxylic acid by the action of alcoholic potassium hydroxide on 2-keto-2 3 4 5-tetrahydro-3-carboline. An equally simple synthesis was effected almost simultaneously by Asahina, Manske and Robinson, who condensed methyl anthranilate with 2-keto-2 3 4 5-tetrahydro-3-carboline (for notation, see p. 492) by the use of phosphorus trichloride (see partial formulae II). Ohta has also synthesised rutaecarpine by heating a mixture of 2-keto-2 3 4 5-tetrahydrocarboline with isatoic anhydride at 195° for 20 minutes. 

IRIS. 1999. Methyl parathion. Integrated Risk Information System. Washington, DC U.S. Environmental Protection Agency. Http //www.ena.gov/iris/subst/index.htm.. April 19, 1999. 

Reduction of a-methyl-fi-hydroxy ketones,2 The r-butyldimethylsilyl ethers of these ketones, in which chelation is difficult, are reduced by lithium aluminum hydride with a high degree of 1,2-anri-selectivity. This reaction can therefore afford either aM ,a/iri-l,3-diols or anti,syn- 1,3-diols with high selectivity. 

Synonyms Methyl bromide monobromomethane methyl fume IRIS 1989... 

Treatment of 2,3-epoxy -2-methyl -4 butanone with boron iri-fluorido etherate in benzene (Kq. 471) gives a good yidd of 2,2-dimethyl-S-oxobutyraidehyde.6 7 This product can only be formed by niigr.it ion of an acyl group. When rearrangement waa conducted at 230 over alumina, methyl isopropyl ketone was isolated, not 4-methyJpenUi>< 2,3-dione as claimed previously.71 Deformylation appears U occur readily on the surface of the alumina catalyst. 

Amino-2-(chloro-difltioro-methyl)-iris-[trifluoromelhyl]- E14a/2.685 (R,C = 0 HCN l R,C = NH)... 

Azido-2-(4-methyl-phenyl)-4-iri-fluoromethyl- E8a. 994 (F -> N,) 5-Azido-2-phenyl-4-trifluoromcthyl-E8a. 994 (F - N, ) 5-Beiizyloxy-2-phenyl-4-tnfluorome-thyl- E10b2. 180 (5-F ->... 

Chlorinated Paraffins. Cl will displace one, two, three, or more hydrogens from the paraffins. These substitution products are referred to as mono (C H2 tiCI), dr (C H Cb). iri (C H2 .>CIi). and so on. Monochloro derivatives include methyl chloride. CHvCI. ethyl chloride. CjHjCI. and propyl chloride. C3H7CI. These are also called alkyl chlorides. Examples of dichlom compounds include methylene dichloride. CHiCL. and ethylene dichloridc, C3H.1CI1 Chloroform. CHCl.v, and... 

The mechanism of iris pigmentation due to latanoprost is unknown. In an in vitro experiment using uveal melanocytes, the addition of latanoprost increased melanin content, melanin production, and tyrosinase activity (18). Alpha-methyl-para-tyrosine, an inhibitor of tyrosinase (the enzyme that transforms tyrosine to levodopa), completely prevented the latanoprost-induced stimulation of melanogenesis. 

Barclay, L. R. C. Sonawane, H. R. MacDonald, M. C. Sterically hindered aromatic compounds. III. Add-catalyzed reactions of 2,4,6-Iri-I-bulyl and 2-methyl-4,6-di-t-butylbenzyl alcohols and chlorides. Can. J. Chem. 1972, 50, 281-290. 

Whereas in L Air du Temps it is the woody-iris character of the methyl ionone that develops in combination with the vetiveryl acetate, in Paris it forms the basis of a violet accord, with Iso E Super as the woody note. Iso E Super, one of the most important of the newer synthetics, is another chameleon-type product combining woody and amber aspects with some of the character of methyl ionone. Used in Paris as part of the L Air du Temps structure, it forms a natural link between the other materials and the violet accord. 

D. 2-Methyl-2-phenyl-4-pentenal (7). A dry, 100-mL three-necked, round-bottomed flask with 14/20 joints is fitted with a magnetic stirrer, reflux condenser, and a rubber septum (Note 16). The flask is charged with 50 iri. of anhydrous tetrahydrofuran (Note 17) and cooled to -78°C in a dry ice/isopropyl alcohol bath, and a solution of butyl 1ithlum (12.0 mmol) in hexane (Note 18) is added with stirring. To this stirred solution is added dropwise via syringe a solution of 3.06 g (12.0 mmol) of diethyl N-benzylideneaminomethyl phosphonate (5) in 5 it of anhydrous tetrahydrofuran, and the colored solution is stirred an additional hour at -78°C. A solution containing 1.20 g (10.0 mmol) of freshly distilled acetophenone In S il of anhydrous tetrahydrofuran is added dropwise, and the cooling bath is removed. The solution is stirred for 1 hr at room temperature and then at reflux for 2 hr. After the solution is cooled to room temperature, it is poured into a 250-nt round-bottomed flask and the solvents are removed under reduced pressure on a rotary evaporator. The yellow residue is partitioned between... 

The Kinetics of Methanol Carbonylation Over RhX, RhY and IrY zeolites Carbonylation of methanol proceeds readily at atmospheric pressure under mild temperature conditions 150°-180°C. This reaction ZCH OH + CO - CH COOCH + HjO produces mainly methyl acetate and water. Acetic acid was detected at high conversions and high temperatures. Traces of dimethyl ether could also form. In most cases the selectivity to methyl acetate was at least 90% in presence of the iodide promotor. 

Examination15 of the green parts of Iris germanica revealed the presence of no 2-methyl carotenoids, although considerable quantities of irones are present in the rhizomes of Iris spp. 

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