Benzyl 4-(dimethylamino)butanoate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 85 g (380 mMol) 4-dimethylamino butyric acid benzylester 19 was stirred with 1 g Pd/C (5%) in 500 ml methanol. The reaction mixture was treated with hydrogen for 4 h. After removing the catalyst, methanol was distilled. A small volume of ethylacetate was added to the remaining residue so that the product would crystallise. The product was then filtered off and washed with ethylacetate. After removing the catalyst, methanol was distilled A small volume of ethylacetate was added to the remaining residue so that the product would crystallise The product was then filtered off washed with ethylacetate

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound, m/e=377.6 ([M−H]−), was produced in analogy with intermediate 1, steps 1 to 4. Thus, 1,8-octanediol was alkylated in step 1 with benzyl bromide, leading to 8-benzyloxy-octan-1-ol, which was oxidized in step 2 to 8-benzyloxy-octanoic acid. This was coupled in step 3 with (R)-3-amino-4-dimethylamino-butyric acid benzyl ester dihydrochloride to produce (R)-3-[8-benzyloxy)-octanoylamino]-4-dimethylamino-butyric acid benzyl ester, which was hydrogenated in step 4.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound, m/e=377.6 ([M−H]−), was produced in analogy with example 1, steps 1 to 4. Thus, 1,8-octanediol was alkylated in step 1 with benzyl bromide, leading to 8-benzyloxy-octan-1-ol, which was oxidized in step 2 to 8-benzyloxy-octanoic acid. This was coupled in step 3 with (R)-3-amino-4-dimethylamino-butyric acid benzyl ester dihydrochloride to produce (R)-3-[8-benzyloxy)-octanoylamino]-4-dimethylamino-butyric acid benzyl ester, which was hydrogenated in step 4.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The title compound, m/e=377.6 ([M−H]−), was produced in analogy with intermediate 1, steps 1 to 4. Thus, 1,8-octanediol was alkylated in step 1 with benzyl bromide, leading to 8-benzyloxy-octan-1-ol, which was oxidized in step 2 to 8-benzyloxy-octanoic acid. This was coupled in step 3 with (R)-3-amino-4-dimethylamino-butyric acid benzyl ester dihydrochloride to produce (R)-3-[8-benzyloxy)-octanoylamino]-4-dimethylamino-butyric acid benzyl ester, which was hydrogenated in step 4.