MyMedR

[Chemical studies on the analgesic indole alkaloids from the traditional medicine (Mitragyna speciosa) used for opium substitute]

Takayama H, Aimi N, Sakai S

Yakugaku Zasshi, 2000 Oct;120(10):959-67.

PMID: 11082707

The leaves of a tropical plant, Mitragyna speciosa Korth. (Rubiaceae), have been traditionally used as a substitute for opium. By phytochemical studies on the constituents of the plant growing in Thailand as well as in Malaysia, several 9-methoxy-Corynanthe-type monoterpenoid indole alkaloids including new natural products were isolated. The structures of these new compounds were elucidated by the modern spectroscopic methods and/or chiral-total syntheses. The chiral total synthesis of (-)-mitragynine, a major component of this plant, was achieved. Potent opioid agonistic properties of mitragynine, which acts on mu- and delta-opioid subtype receptors, and of mitragynine pseudoindoxyl, whose analgesic activity is more potent than that of morphine, were clarified in in vitro experiments. The essential structural features in mitragynine for revealing the analgesic activity were elucidated by pharmacological evaluation of the natural and synthetic mitragynine derivatives.

Factors affecting adherence to behaviours appropriate for the prevention of pressure injuries in people with spinal cord injury from Malaysia: a qualitative study

Mohamad Hashim N, Yusof ANM, Engkasan JP, Hasnan N

Spinal Cord, 2021 Jul;59(7):777-786.

PMID: 33230272 DOI: 10.1038/s41393-020-00586-1

STUDY DESIGN: Focus group qualitative study.

OBJECTIVES: To explore factors affecting adherence to behaviours appropriate for the prevention of pressure injuries (PIs) in people with spinal cord injury (SCI) in Malaysia.

SETTING: University Hospital, Malaysia METHODS: Four sets of focus group interviews were conducted, each with 5-10 participants, totalling 30 people with SCI. A trained interviewer used structured interviews designed to explore participants' experiences of complying with recommended behaviours for the prevention of PIs. All interviews were digitally recorded, transcribed, and analysed utilising thematic analysis.

RESULTS: The factors that affected participants' adherence are classified into four main themes: (a) educational aspects, (b) internal drive, (c) social and environmental factors, and (d) post-SCI physiological changes.

CONCLUSIONS: This qualitative study provides initial exploratory evidence regarding the thoughts, experience, and opinions pertaining to PI preventive behaviours within the Malaysian SCI population. The emerging themes contribute to an in-depth understanding of the competency of the Malaysian healthcare system in PI prevention, personal and societal factors influenced by the socio-demographic backgrounds, and disease-related factors that influence the adherence to such preventive interventions.

Anthraquinones from hedyotis herbacea

Permana D, Lajis NH, Othman AG, Ali AM, Aimi N, Kitajima M, et al.

J Nat Prod, 1999 Oct;62(10):1430-1.

PMID: 10543909

A new anthraquinone, 2-hydroxymethyl-10-hydroxy-1,4-anthraquinone (1), was isolated from Hedyotis herbacea along with three other known derivatives: 1,4-dihydroxy-2-hydroxymethylanthraquinone (2); 2, 3-dimethoxy-9-hydroxy-1,4-anthraquinone; and 1,4-dihydroxy-2, 3-dimethoxyanthraquinone. The structure of 1 was determined based on analysis of its spectroscopic data.

Methyl chanofruticosinates from leaves of Kopsia flavida Blume

Husain K, Jantan I, Kamaruddin N, Said IM, Aimi N, Takayama H

Phytochemistry, 2001 Jun;57(4):603-6.

PMID: 11394866

Three new indole alkaloids with methyl chanofruticosinates skeletal system, viz., methyl 12-methoxy-N1-decarbomethoxychanofruticosinate, methyl 12-methoxychanofruticosinate and methyl 11,12-dimethoxychanofruticosinate, in addition to methyl 11,12-methylenedioxy-N1-decarbomethoxychanofruticosinate, have been isolated from the leaves of Kopsia flavida Blume. The structures of these three new indole alkaloids were assigned by NMR spectral data using various 2D-techniques.

A new prenylated dihydrochalcone from the leaves of Artocarpus lowii

Jamil S, Sirat HM, Jantan I, Aimi N, Kitajima M

J Nat Med, 2008 Jul;62(3):321-4.

PMID: 18404311 DOI: 10.1007/s11418-008-0226-3

A new prenylated dihydrochalcone, 2',4'-dihydroxy-4-methoxy-3'-prenyldihydrochalcone (1), along with two known compounds, 2',4',4-trihydroxy-3'-prenylchalcone (2) and 2',4-dihydroxy-3',4'-(2,2-dimethylchromene)chalcone (3) were isolated from the leaves of Artocarpus lowii. The structures of 1-3 were elucidated by spectroscopic methods and by comparison with data reported in the literature. Compounds 1-3 showed strong free radical scavenging activity towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) measured by electron spin resonance (ESR) spectrometry.

Two new methyl chanofruticosinates from Kopsia flavida blume

Husain K, Jantan I, Said IM, Aimi N, Takayama H

J Asian Nat Prod Res, 2003 Mar;5(1):63-7.

PMID: 12608641

Two new indole alkaloids with the methyl chanofruticosinate skeletal system viz., methyl 3-oxo-12-methoxy-N1-decarbomethoxy-14,15-didehydrochanofruticosinate (1) and methyl 3-oxo-11,12-methylenedioxy-N-decarbomethoxy-14,15-didehydrochanofruticosinate (2), together with four known compounds, methyl 12-methoxy-N1-decarbomethoxychanofruticosinate, methyl 12-methoxychanofruticosinate, methyl 11,12-dimethoxychanofruticosinate and methyl 11,12-methylenedioxy-N1-decarbomethoxychanofruticosinate, were isolated in continuing studies on the leaves of Kopsia flavida Blume. The structures of the new indole alkaloids were assigned by NMR spectral data using various 2D-techniques.

7-Methoxyglycomaurin: a new carbazole alkaloid from Glycosmis rupestris

Rahmani M, Ling CY, Sukari MA, Ismail HB, Meon S, Aimi N

Planta Med, 1998 Dec;64(8):780.

PMID: 17253329

Isolation and Asymmetric Total Synthesis of a New Mitragyna Indole Alkaloid, (-)-Mitralactonine

Takayama H, Kurihara M, Kitajima M, Said IM, Aimi N

J Org Chem, 1999 Mar 19;64(6):1772-1773.

PMID: 11674259

Isolation and bioactivities of constitutents of the roots of Garcinia atroviridis

Permana D, Lajis NH, Mackeen MM, Ali AM, Aimi N, Kitajima M, et al.

J Nat Prod, 2001 Jul;64(7):976-9.

PMID: 11473441

Two new prenylated compounds, the benzoquinone atrovirinone (1) and the depsidone atrovirisidone (2), were isolated from the roots of Garcinia atroviridis. Their structures were determined on the basis of the analysis of spectroscopic data. While compound 2 showed some cytotoxicity against HeLa cells, both compounds 1 and 2 were only mildly inhibitory toward Bacillus cereus and Staphylococcus aureus.

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