Amines hydroxy acids

With A5 acids (such as the C20 acids in meadowfoam oil), the 8 lactone is formed in high yield when the acid is refluxed for 3 h with perchloric acid in dichloromethane. The proportion of 8 to y lactone depends on the reaction solvent. In hexane, the ratio is 6 1 and in dichloromethane almost 40 1. The 8-lactone is much more reactive than its y isomer. It can be converted to hydroxy amides (amines), hydroxy acids (alkali), and alkoxy esters (alcohol and acid) wifli the reagents indicated in parentheses. 

The reaction is of practical importance in the vulcanization of siUcone mbbers (see Rubber compounding). Linear hydroxy-terrninated polydimethyl siloxanes are conveniently cross-linked by reaction with methyldiethoxysilane or triethoxysilane [998-30-1]. Catalysts are amines, carboxyflc acid salts of divalent metals such as Zn, Sn, Pb, Fe, Ba, and Ca, and organotin compounds. Hydroxy-terrninated polysiloxanes react with Si—H-containing polysiloxanes to... 

Reaction of cyanohydrins with absolute ethanol in the presence of HCl yields the ethyl esters of a-hydroxy acids (3). A/-substituted amides can be synthesized by heating a cyanohydrin and an amine in water. Thus formaldehyde cyanohydrin and P-hydroxyethylamine lead to A/- (P-hydroxyethyl)hydroxyacetamide (4). 

Water repellant To impart water-resistant properties, particularly in greases Aliphatic amines, hydroxy fatty acids and some organic silicone polymers... 

Two reactions for the production of L-phenylalanine that can be performed particularly well in an enzyme membrane reactor (EMR) are shown in reaction 5 and 6. The recently discovered enzyme phenylalanine dehydrogenase plays an important role. As can be seen, the reactions are coenzyme dependent and the production of L-phenylalanine is by reductive animation of phenylpyruvic add. Electrons can be transported from formic add to phenylpyruvic add so that two substrates have to be used formic add and an a-keto add phenylpyruvic add (reaction 5). Also electrons can be transported from an a-hydroxy add to form phenylpyruvic add which can be aminated so that only one substrate has to be used a-hydroxy acid phenyllactic acid (reaction 6). 

N-Methyl-N-f2-Nitroxy propyl) Nitramine. (Me2NENA N-(2-NitroxypropyI) methyl nitramine. (02N)N(CH3).(CH2CH(0N02).CH3, mw 179.16, N 23.46%, OB to C02 -66.80%, pale yellow oil, mp 22—23°, d 1.320g/cc at 25/4°, RI 1.478 at 25°. Prepn from 2-hydroxy-propylamine after nitration with 98% nitric acid at 10° by reaction of the amine-nitric acid mixt with acetic anhydride acetyl chloride at 35°. Reaction mixt poured on ice. Yield is 74%. No expl properties listed Reft 1) Beil - not found 2) Blomquist, OSRD 4134, 45 119 (1944)... 

A number of ketones, pharmaceutical compounds, alcohols and hydroxy acids have also been resolved on this phase [724,765-767]. A chiral polysiloxane phase with tartramide substituents has been used for the separation of enantiomers capable of hydrogen bonding interactions with the stationary phase, such as enantiomers containing carboxylic, hydroxyl and amine functional groups [768]. 

A series of N-substituted narceine amides (Section III,D,1) was prepared from 101 under the action of primary amines (100). Acid-catalyzed dehydration transformed these amides to corresponding imides (ene lactams) of the ( )-narceine imide (117) type (100). Similar transformations were performed in the hydrastine series (101). JV-Methylhydrastine (98) when treated with dilute ammonium hydroxide gave hydroxy lactam 127, which was dehydrated to (Z)-fumaridine (113) (5). Sodium borohydride was able to reduce the stilbene double bond in 98 to produce saturated lactone 132 (5). 

Hydroxynitrile lyases (HNLs or oxynitrilases) catalyze C—C bond-forming reactions between an aldehyde or ketone and cyanide to form enantiopure cyanohydrins (Figure 1.15), which are versatile building blocks for the chiral synthesis of amino acids, hydroxy ketones, hydroxy acids, amines and so on [68], Screening of natural sources has led to the discovery of both... 

Aliphatic aldehydes, 13 571 physical properties of, 2 60t syntheses of, 12 187 Aliphatic a-hydroxy acids, 14 130 Aliphatic amine/polysulfide co-curing agent systems, 10 410... 

Phenolic resins also find use in varnishes, electrical insulation, and in other protective coatings. Heat-settings adhesives which are based on phenolics find use in producing plywood. These also find use in the production of ionexchange resins having amine, sulphonic acid, hydroxy or phosphoric acid functional groups. 

Isocyanates are quite reactive and they react with compounds which contain active hydrogen such as hydroxy, amine, carboxylic acids, amide, urea, etc. They can also undergo addition reaction ... 

At that time, as now, the enantiomers of many chiral amines were obtained as natural products or by synthesis from naturally occurring amines, a-amino acids and alkaloids, while others were only prepared by introduction of an amino group by appropriate reactions into substances from the chiral pool carbohydrates, hydroxy acids, terpenes and alkaloids. In this connection, a recent review10 outlines the preparation of chiral aziridines from enantiomerically pure starting materials from natural or synthetic sources and the use of these aziridines in stereoselective transformations. Another report11 gives the use of the enantiomers of the a-amino acid esters for the asymmetric synthesis of nitrogen heterocyclic compounds. 

Unnatural amino acids are added to the growth medium in most experiments. There are a large number of amino acid and amine transporters that are relatively nonspecific and which may help to transport the unnatural amino acids into cells. From measurements of cytoplasmic levels of amino acids, it is found that a large number of unnatural amino acids are efficiently transported to the E. coli cytoplasm in millimolar concentrations. Highly charged or hydrophilic amino acids may require derivatization (e.g., esterification, acylation) with groups that are hydrolyzed in the cytoplasm. Metabolically labile amino acids or analogues (e.g., a-hydroxy acids, A-methyl amino acids) may require strains in which specific metabolic enzymes are deleted. 

Biochemical reactions include several types of decarboxylation reactions as shown in Eqs. (1)-(5), because the final product of aerobic metabolism is carbon dioxide. Amino acids result in amines, pyruvic acid and other a-keto acids form the corresponding aldehydes and carboxylic acids, depending on the cooperating coenzymes. Malonyl-CoA and its derivatives are decarboxylated to acyl-CoA. -Keto carboxylic acids, and their precursors (for example, the corresponding hydroxy acids) also liberate carbon dioxide under mild reaction conditions. 

Here, as with the 4-HO-DMT (psilocin) and the 4-HO-DET entries, some care must be made with the use of the term "acetate" or "phosphate." As these materials are both bases (tertiary amines) and acids (hydroxy indoles), they are in effect internal salts. For stability, they are usually converted into salts (at the amine end) or esters (at the phenolic end), or both. In this context, the term "acetate" can mean either modification, a salt or an ester involving acetic acid. And, of course, a phosphate can be either a salt or an ester. I will try to append the additional term "salt" or "ester" whenever this ambiguity is possible. In all of these studies, the acetate is the ester, and some of these are free bases, some are the hydrochloride salts and some are the fumarate salts. 

Alcohols Carboxylic acids Phenols Primary and secondary amines Oximes Nitro compounds (with a-H atoms) Nitriles (with a-H atoms) Polyhydroxyalcohols Amino alcohols Hydroxy acids Polyprotic acids Polyphenols... 

Oxazolines.1 Hydroxy amides, prepared from p-hydroxy amines and acid chlorides, are converted into 2-oxazolines with the Mitsunobu reagent at 0 — 25° (equation I). 

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