Binh Duong Vu

Objectives: To optimally extract the potential phytochemical “6-shogaol” from fermented shogaol-enriched ginger. Methods: Extraction process parameters were investigated using 6-shogaol as a marker. Results: The suitable parameters of the 6-shogaol extraction process: Hot extraction using reflux equipment, solvent of 90% ethanol, solvent/herb ratio of 15/1, temperature of 70ºC, duration of 90 minutes, and two-time extraction. The 6-shogaol extraction efficiency was 89.61 ± 0.68%. Conclusion: The optimal process for 6-shogaol extraction from fermented shogaol-enriched ginger has been studied.

Mục tiêu: Xây dựng phương pháp định lượng đồng thời 6-shogaol, 6-gingerol, 8-gingerol, 10-gingerol trong gừng bằng phương pháp sắc ký lỏng hiệu năng cao (high-performance liquid chromatography - HPLC) ứng dụng trong kiểm nghiệm nguyên liệu và thành phẩm. Phương pháp nghiên cứu: Khảo sát, lựa chọn điều kiện sắc ký. Thẩm định phương pháp phân tích theo hướng dẫn chung của ICH (International Conference on Harmonisation). Kết quả: Nghiên cứu đã lựa chọn được các điều kiện sắc ký gồm cột InertSustain AQ - C18 (150 x 4,6mm, 5µm), detector UV bước sóng 280nm; hệ dung môi pha động: Acetonitril (C) và acid acetic 0,1% (A) chạy theo chương trình gradient (0 - 10 phút, C 50%; 10 - 40 phút, C 50% - 90%; 40 - 45 phút, C 90% - 100%; 45 - 50 phút, C 100% - 50%); thể tích bơm mẫu là 10µL; tốc độ dòng pha động là 1,0 mL/phút. Thẩm định phương pháp sắc ký về tính tương thích hệ thống, độ đặc hiệu, độ chọn lọc, độ đúng và độ chính xác. Kết luận: Đã xây dựng được phương pháp định lượng đồng thời 6-shogaol, 6-gingerol, 8-gingerol, 10-gingerol. Kết quả thẩm định cho thấy, phương pháp phân tích đáp ứng yêu cầu theo hướng dẫn của ICH.

Memantine hydrochloride (MH) is a first-line therapeutic drug approved by the US FDA for the management of moderate to severe Alzheimer's disease. This study involves the synthesis of memantine hydrochloride from 1-bromo-3,5-dimethyladamantane through a reaction with thiourea. The research results showed that the solvent reaction was propylene glycol (PG); the total time reaction was 5.5 hours, the temperature reaction in the first stage was 160o C and in the second stage was 80o C; the overall yield was 82.44%. The reaction intermediates were confirmed by the IR, MS,1 HNMR, and 13C-NMR spectra.

: A new, simple method for the synthesis of N,N-diethyl-m-methylbenzamide (DEET) from m-toluic acid and diethylamine using 1,1'-carbonyl-di-(1,2,4-triazole) (CDT) as a coupling agent has been performed. The basic principles of activated carbonyls have been explored with the ability to prepare new amides easily. All reaction by-products are water-soluble as well as removed by filtration, the reaction could be purified easily in an aqueous solution by liquid-liquid extraction, and the product DEET was high purity. This experimental efficiency is about 94-95%, purity (HPLC): 97-98%.

Thalidomide (1) (N-phthalimidogluatarimide) was first marketed in West Germany by Chemie Grunelthal GmbH as a clinically effective non-barbiturate sedative-hypnotic in 1957.1–3 This drug was widely...

Amantadine hydrochloride (1, Scheme 1) is an important antiviral and anti-Parkinson drug.1–5 However, previous methods for its preparation,4–32 in yields as high as 50-58%,4,6,22 have had safety an...

A simple and economical process for producing amantadine hydrochloride (1) on a 250 g scale, an antiviral and anti-Parkinson drug, has been developed. Several methods for the preparation of 1 through intermediate N-(1-adamantyl)-acetamide (4) in four or three steps were reported. These procedures started with adamantine (2) or 1-bromoadamantane (3), acetonitrile, and sulfuric acid by using the Ritter-type reaction to obtain N-(1-adamantyl)-acetamide, which was deacetylated to afford 1-amino-adamantane (5) and then the salt formed with anhydrous HCl gives 1 with the overall yield of 1 being 50–58%. In this article, a two-step procedure for the synthesis of 1 from 1-bromadamantane (3) and formamide via N-(1-adamantyl)-formamide (6) in two steps with an overall yield of 88% was reported. In this procedure, the preparation of 6 from 3 is a key step with a yield of 94%, followed by the hydrolysis of 6 with an aq. solution of HCl to give 1 in high yield (93%). The procedure was also carried out under optimal conditions established to reduce the use of toxic reagents or solvents and was carried out in one pot to make it more environmentally friendly. The procedure can be considered as more suitable for the large-scale production of 1. The structures of product 1 and intermediate 6 were confirmed by IR, MS, ¹H NMR, ¹³C NMR.

This work presents a predominant cost-saving process for the industrial scale synthesis of memantine hydrochloride (1) from 1,3-dimethyladamantane (2) by a two-step method in which both steps were carried out in one-pot. The conversion of 2 to N-(3,5-dimethyladamantane-1-yl)acetylamide (3) was synthesized first in mixture of sulfuric acid 96-98% and nitric acid 64-65% at 25 ºC for 2.5 h and then in acetonitrile at 40 ºC for 3.5 h as a key step. The yield of this process reached to 98%. Next, the deacetylation of 3 with potasium hydroxide in mixture of water-ethylene glycol at 140 ºC for 15 h to get memantine base which was then converted into memantine hydrochloride (1) by aq. HCl 14% (yield of 93%). Overall yield of this synthetic route was 91.65%. The advantages of this process is saving time, solvents, reagents and giving a higher yield as compared to reported procedures.