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The bulbs of Ledebouria socialis (Hyacinthaceae) yielded the benzocyclobutene homoisoflavonoid, (R)-2',5-dihydroxy-3',4',7-trimethoxyspiro{2H-1-benzopyran-3-(4H)-9-bicyclo[4.2.0]octa[1,3,5]triene}-4-one, socialinone (1). Ledebouria ovatifolia yielded (2ε,3R)-2,5-dihydroxy-7-methoxyspiro[2H-1-benzopyran-3(4H), 5'(6'H)-cyclobuta[f][1,3]benzodioxol]-4-one (2) and the homoisoflavanone, (E)-3-(3',4'-dihydroxybenzylidene)-5,7-dihydroxychroman-4-one, ovatifolionone (5), the dihydrochalcone, 4,4'-dihydroxy-2',6'-dimethoxydihydrochalcone (3), and xanthone, 1,6-dihydroxy-2,3,5-trimethoxy-8-methyl-9H-xanthen-9-one (4) along with 21 known compounds. Structures were determined using spectroscopic techniques. The anti-inflammatory activities of the homoisoflavonoids and xanthones isolated were evaluated against cyclooxygenase-1 and -2 isoenzymes. (R)-3-(3',4'-Dihydroxybenzyl)-7-hydroxy-5-methoxychroman-4-one (7), (E)-3-(3',4'-dihydroxybenzylidene)-7-hydroxy-5-methoxychroman-4-one (10), 1,3,6-trihydroxy-2-methoxy-8-methylxanthen-9-one (6) and ovatifolionone acetate (5Ac) exhibited significant activity against cyclooxygenase-2 at <10μM., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The stem bark of Croton gratissimus (Euphorbiaceae) yielded four cembranolides, including the first reported example of a 2,12-cyclocembranolide, (+)-[1R*,2S*,7S*,8S*,12R*]-7,8-epoxy-2,12-cyclocembra-3E,10Z-dien-20,10-olide, whose structure was confirmed by means of single crystal X-ray analysis. This compound showed moderate activity against the PEO1 and PEO1TaxR ovarian cancer cell lines., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Five 3-hydroxy-type homoisoflavonoids, 3,5-dihydroxy-7,8-dimethoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7-methoxy-3-(3',4'-dimethoxybenzyl)-4-chromanone, 3,5-dihydroxy-7,8-dimethoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone, 3,5,6-trihydroxy-7-methoxy-3-(3'-hydroxy-4'-methoxybenzyl)-4-chromanone and 3,5,7-trihydroxy-3-(3'-hydroxy-4'methoxybenzyl)-4-chromanone in addition to the nortriterpenoid, 15-deoxoeucosterol, have been isolated from the dichloromethane extract of the bulbs of Pseudoprospero firmifolium, the sole representative of the tribe Pseudoprospereae of the subfamily Hyacinthoideae of the Hyacinthaceae.

The bufadienolides, rubellin and riparianin were isolated from the bulbs of Drimia macrocentra and Urginea riparia (Hyacinthaceae) respectively. Rubellin and riparianin contain a carbohydrate moiety doubly linked to the bufadienolide aglycone at the C-2 and C-3 positions. Riparianin showed moderate activity when tested against MCF7 (breast), TK10 (renal) and UACC62 (melanoma) cell lines.

Two bufadienolides, 3beta,16beta-dihydroxy-5beta-bufa-20,22-dienolide and 16beta-hydroxy-5beta-bufa-20,22-dienolide-3beta-O-beta-d-galactoside, have been isolated from bulbs of the poisonous South African geophyte Drimia depressa (Hyacinthaceae).

The combined hexane/CH(2)Cl(2) extract of the stem bark of Teclea gerrardii (Rutaceae: Toddalioideae) has yielded two acridone alkaloids, 3-hydroxy-1-methoxy-N-methylacridone (tegerrardin A) (1) and 3-hydroxy-N-methyl-1-(gamma,gamma-dimethylallyloxy)acridone (tegerrardin B) (2), three known acridones (3-5), two known furoquinolines (6,7), and the acridone precursor tecleanone (8). Arborinine (3) and evoxine (6) displayed moderate antiplasmodial activity against the CQS D10 strain of Plasmodium falciparum, with IC(50) values of 12.3 and 24.5 microM, respectively.

Bulbs of the ethnomedicinal hyacinthac Urginea lydenburgensis have yielded two bufadienolides, 16beta-acetoxy-3beta,14beta-dihydroxy-19-formyl-bufa-4,20,22-trienolide (scillicyanosidin) and 4beta,8beta,11alpha,14beta-tetrahydroxybufa-5,20,22-trienolide-12-one, 2alpha,3beta-O-4,6-dideoxy-L-glucose (lydenburgenin).

Toddaliopsins A-D, four novel 1,2,3-trioxygenated acridone alkaloids, have been isolated from the leaves of Toddaliopsis bremekampii. Toddaliopsins B-D are the first reported acridone alkaloids with substituted N-methyl groups, in the light of which the chemotaxonomic relationship of Toddaliopsis and Vepris is discussed. Toddaliopsin C possesses moderate anti-inflammatory activity, which may be related to the hydroxy group present at C-1.

The chloroform and ethyl acetate extracts of the leaves of Teclea natalensis have yielded two furoquinoline alkaloids, 6-[(2,3-epoxy-3-methylbutyl)oxy]-4,7-dimethoxyfuro[2,3-b]quinoline and 4,7-dimethoxy-6-[(3-methyl-2-butenyl)oxy]furo[2,3-b]quinoline, and the known alkaloids 4,7-dimethoxy-8-[(3-methyl-2-butenyl)oxy]furo[2,3-b]quinoline, flindersiamine and dictamnine.

Two bufadienolides, 6beta-acetoxy-3beta,8beta,14beta-trihydroxy-12-oxobufa-4,20,22-trienolide and 14beta-hydroxybufa-3,5,20,22-tetraenolide were isolated from the dichloromethane extract of the bulbs of Drimia robusta and the methanol extract of the bulbs of Urginea epigea, respectively. The bulbs of Drimia robusta also yielded several known compounds, 6beta-acetoxy-3beta,8beta,12beta,14beta-tetrahydroxybufa-4,20,22-trienolide (12beta-hydroxyscillirosidin) from the dichloromethane extract and three common aromatic acids, 4-hydroxy-3-methoxybenzoic acid, 3,4-dihydroxybenzoic acid, and trans-3-(4'-hydroxyphenyl)-2-propenoic acid from the ethyl acetate extract.