A process for the preparation of Compound I of the formula comprising the steps of a) reacting Compound 1 of the formula with Compound 2 of the general formula where R 1 is a leaving group and with an acid, in a suitable solvent to afford Compound 3 of the formula b) reacting Compound 3 in a reductive amination reaction with a primary or secondary amine (HNR 2 R 3) where R 2 and R 3 are hydrogen or C 1 -C 6 alkyl; mediated by a Lewis acid followed by reaction with a suitable hydride donor or a combination of a catalysts and hydrogen gas, to afford Compound 4 of the formula wherein X is an inorganic or organic counter ion; c) subsequently reacting the salt of Compound 4 with i -PrOH /H 2 SO 4 or free basing first with NaOH and then with an appropriate acid/solvent mixture, to afford Compound 5 of the formula d) reacting Compound 5, or a salt thereof, in a reductive amination, in an appropriate solvent and using a hydride source, with Compound 6 of the formula to afford Compound 7 of the formula, e) which is then reacted with an acid, in the presence of NH 2 OH, or its salt, and a suitable solvent to afford Compound 8 of the formula f) which is further reacted with an acid, a base, and heated to 45 - 70 °C in an appropriate solvent or solvent mixture to afford Compound 9 of the formula g) subsequently removing the protecting group to afford Compound 10 of the formula h) which is then reacted with Compound 11a of the formula where X is a leaving group to afford Compound I, which is then crystallized from a suitable solvent mixture. a) reacting Compound 1 of the formula with Compound 2 of the general formula where R 1 is a leaving group and with an acid, in a suitable solvent to afford Compound 3 of the formula b) reacting Compound 3 in a reductive amination reaction with a primary or secondary amine (HNR 2 R 3) where R 2 and R 3 are hydrogen or C 1 -C 6 alkyl; mediated by a Lewis acid followed by reaction with a suitable hydride donor or a combination of a catalysts and hydrogen gas, to afford Compound 4 of the formula wherein X is an inorganic or organic counter ion; R 2 and R 3 are hydrogen or C 1 -C 6 alkyl; mediated by a Lewis acid followed by reaction with a suitable hydride donor or a combination of a catalysts and hydrogen gas, to afford Compound 4 of the formula wherein X is an inorganic or organic counter ion; c) subsequently reacting the salt of Compound 4 with i -PrOH /H 2 SO 4 or free basing first with NaOH and then with an appropriate acid/solvent mixture, to afford Compound 5 of the formula d) reacting Compound 5, or a salt thereof, in a reductive amination, in an appropriate solvent and using a hydride source, with Compound 6 of the formula to afford Compound 7 of the formula, e) which is then reacted with an acid, in the presence of NH 2 OH, or its salt, and a suitable solvent to afford Compound 8 of the formula f) which is further reacted with an acid, a base, and heated to 45 - 70 °C in an appropriate solvent or solvent mixture to afford Compound 9 of the formula g) subsequently removing the protecting group to afford Compound 10 of the formula h) which is then reacted with Compound 11a of the formula where X is a leaving group to afford Compound I, which is then crystallized from a suitable solvent mixture.