1.2- Diamino- 4-methoxybenzene

The initial stages of the preparation of the macrocycle 205c, i.e., the precursor of 200c proceed in a different way. Quinoxahne 207a with a butylene substitute has been obtained by condensation of 1,2-diamino-4-methoxybenzene with ethyl 2-oxo-hex-5-enoate. The subsequent four stages (il—i4) of the processes proceed similarly to the stages (i2—i4, i7) as in the synthesis of compounds 205a,b. 

The alpha acids represent a mixture of several homologues and isomers (3). The main component, called humulone, was discovered by Lintner and Schnell in 1904 (4). The purification was described by Wollmer (5), who succeeded in obtaining a crystalline derivative of the alpha acids by reaction with 1,2-diaminobenzene (1,2-phenylenediamine). These 1 1 complexes are fully dissociated in solution (6). After several recrystallizations the humulone complex is isolated in the pure state, while the complexes of the other alpha acids remain in solution. The course of the purification process may be monitored via NMR (7). Acid decomposition of the humulone complex and recrystallization from acetic acid water furnishes very pure humulone (pale-yellow crystals melting point 72°C). Humulone itself has little or no bitter taste. Other crystalline derivatives of the alpha acids have been obtained by complexation with 1,2-diamino-4-methylbenzene, 1,2-diamino-4,5-dimethylbenzene, 2,6-diaminopyridine and 1,2-diamino-4-methoxybenzene (8), while a phenylurethane derivative has also been prepared (9). 

Figure 4. Separation of selected aromatic amines on a basic WCOT glass capillary column with stationary phase Carbo wax 20 M solvent, 2-butanone. Peak identities 1, 1,2-diaminotoluene 2, 2,4-diaminotoluene 3, N,N-dipheny famine 4, 1-aminonaphthalene 5, 2-aminonaphthalene 6, 2,4-diamino-l-methoxybenzene.

DIAMINOANISOLE BASE m-DIAMINOANISOLE l,3-DIAMINO-4-METHOXYBENZENE 2,4-DIAMINO-l-... 

C.I. 76051 C.I. OXIDATION BASE 12A 2,4-DAA SULFATE 2,4-DIAMINOANISOLE SULPHATE 2,4-DIAiMINO-ANISOL SULPHATE 2,4-DIAMINO-l-METHOXYBENZENE l,3-DIAMINO-4-METHOXY-BENZENE SULPHATE 2,4-DIAMINO-l-METHOXY-BENZENE SULPHATE 2,4-DIAMINOSOLE SULPHATE... 

Synonyms/Trade Names 1,3-Diamino-4-methoxybenzene 4-Methoxy-1,3-benzene-diamine 4-Methoxy-m-phenyiene-diamine (Synonyms of saits vary depending upon the specific compound.)... 

Diaminoanisole m-Diaminoanisole 1,3-diamino-4-methoxybenzene. See 4-Methoxy-m-phenylenediamine... 

DAA sulfate 2,4-Diaminoanisol sulfate t ri hyd rate 1,3-Di am i no-4-methoxybenzene sulfate trihydrate 2,4-Diamino-1-methoxybenzene sulfate trihydrate 4-Methoxy-... 

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