GB2120650A - Rooperol derivatives - Google Patents

Abstract

Organic compounds comprising a C5 carbon chain having at least one of the end C atoms in the chain joined by a double or triple bond.

Description

SPECIFICATION Rooperol derivatives FIELD OF THE INVENTION This invention relates to chemical compounds including and related to a new substance which the applicant has named rooperol, and its derivatives; as well as methods for their isolation, synthesis and their incorporation in and use of pharmaceutical products containing them, for humans and animals.

In particular, the compounds and compositions of the invention are used as antimicrobial, particulariy antibacterial bacteriostatic, virostatic and fungistic agents. The compounds also show important properties in relation to the treatment and prevention of cancerous conditions and leukemia.

DEFINITIONS OF THE INVENTION According to the invention there is provided a compound having the general formula:

in which the bonds between carbons 1 and 2 and carbons 4 and 5 are unsaturated and R1 and R2 and R5 and R6 may, where apt, be hydrogen or other substituent groups; and R3 and R4 may be hydrogen or a substituent group or both taken together may be =O or =S; and A or B may be hydrogen or a substituent or unsubstituted alkyl, aryl or heterocyclic or other substituent.

in one aspect of the invention A and/or B may be a group

in which R7 and R8 may be the same or different and may be hydrogen, alkyl, aryl, heterocylic or acyl or other substituent groups including glycoside moieties; or A and/or B may constitute another aromatic system such as naphthyl, phenanthryl or the like with a free or protected hydroxy group in the meta and/or para position with respect to C-i' or a heterocyclic system which may include substituent groups.

In a preferred form of the invention the compounds have the formula

in which A, B, R', R2, R3 and R4 have the same meanings as above.

A particular group of compounds of the present invention has the general formula (IUPAC system):

in which R', R2, R3 and R4 may be the same or different and may be hydrogen, alkyl, aryl, heterocyclic or acyl or other substituent groups including glycoside moieties, the benzene rings being optionally further functionalised with one or more substituent groups, and the hydrogen atoms in the aliphatic carbon chain may be optionally replaced by one or more substituent groups; (for example one or both hydrogens in the 3-position may be replaced by halogen, hydroxyl, amino, -SH, =O or =S or the like; together with homologues, analogues and geometric isomers thereof; and, in particular the transisomer.

The parent compound of this latter group of compounds has been named ROOPEROL (1) and was obtained from Hypoxis rooperi, H. nitida, H. obtusa, H. rigidula, H. latifolia and other Hypoxis species as well as from Splloxene schlechteri as a diglucoside. Rooperol may be named according to the IUPAC system as a derivative of pentene as follows: (E)-1 ,5-bis(3',4'-dihydroxyphenyl)pent4-en-1 -yne.

However, to avoid complicated positional nomenclature problems a trivial nomenclature system based on the parent compound 1 ,5-bisphenylpent-4-en-1 -yne will be used and consecutive carbon atom numbering continuing around the phenyl ring as determined by substituent priorities: some of the preferred compounds being as follows:

R' R2 R3 R4 1 H H H H 1 a FD-glucoside H ,B-D-glucoside H 1 b jB-D-glucoside H H H 1c H H ,B-D-glucoside H 1 d CH3CO CH3CO CH3CO CH3CO 1 e H s-D-glucoside H p-D-glucoside if OMe OMe OMe OMe Rooperol diglucoside la will therefore be trans-rooperol 8,3'-di--D-glucopyrnnoside.

This diglucoside is the major rooperaol derivative in all the Hypoxis species investigated. Mono-, other di-, tri- and tetra-glucosides are included with the scope of the invention.

It is probable that rooperal and its derivates exist throughout the Hypoxidaceae family and in other plant families.

Preferred compounds of the invention include: - the simple acyl derivates such as the acetate of rooperaol, i.e. trans-rooperol 8,9,3',4'- tetraacetate (Id) as well as the peracetates of la--(lc), le and of other di-, tri- and tetraglucosides, testers derived from other carboxylic acids such as propanoates along the homologous series to palmitates, oleates and the like, -sulphonates derived from p-toluene sulphonic acid and other sulphonic acids, wethers derived from the phenolic or glucosidic (or glycosidic) hydroxy groups, especially the phenyl methoxy- or ethoxy groups, or the aromatic methylene dioxy group;; - acetals and acetonides and related functions in the carbohydrate moiety and hemiesters derived from dicarboxylic acids.

In addition the compounds of this invention encompass glycosides derived from sugars other than glucose, such as arabinose, galactose, mannose, rhamnose, maltose and the like.

The hydroxy groups (free of derivatised) in rooperol may be replaced by hydrogen or change their position or extra hydroxy groups may be added. In addition these hydroxyl groups may be replaced by other substituent groups such aslkyl-(CH3-, CH3CH2- etc)., amino-(NH2, -NHR, -NR2 and N+R3 or their salts), nitro-, halogenyl (Cl-, Br-, I and F-), carboxylic acid- and sulphonic acid (or their salts) or aryl groups.

The 1,2 and/or 4/5-dihydro derivatives of all the above compounds are also within the scope of the invention, and hdyrogen atoms on carbons 1, 2, 3, 4 and 5 may be replaced by one or more alkyl and/or aryl substituents (either as such or functionalised as described above).

The preferred compounds of this invention are as follows: trans-Rooperol (I) Ezymatic hydrolysis of the 8,3'-di-p-1-glucoside (la) of rooperol with ss-glucosidase furnished rooperol (I), m.p. 1 360C (Found: C, 70.92; H, 5.10, C17H14O4'.+H2O requires C, 70,09 H, 5.19; H2O, 3.09%), (KBr) 3200-3500 (H bonded OH), 960 cm~1 (trans CW=CH), mX (EtOH) 260 (E 10348), 294 (E 4327), 301 nm (E 4045); a (CD3CD2OD), 3.41 [2H, d, CH2 on C(3), J 5.0 Hz], 5.37 (4H, broad s, 4 x OH), 6.10 [1 H, dt, J 15.0 Hz, proton on C(3)j, 6.67 [1 H, d, J 15.0 Hz, proton on C(5)1, 6.80-7.15 (6H, m, Arom H). The compound (I) darkens rapidly on exposure to air.

trans-Rooperol 8,3'-di-B-D-glucoside (1 a) This compound was obtain in high yield by extraction of corms of various Hypoxis species (H.

rooperi, H. rigidula, H. nitida, H. Iatifolia and others including Spitoxene schlechtei as illustrated in Example 1. It is a crystalline compound m.p. 147-148 C, [a] - 1 09.S0 (c 0.45, meOH) (Found: C 54.67, H 5.87%. C29H34O,4 . 2H2O requires C54.20, H 5.95, H2O, 5.61% rnax(KBr)31 50-3500 cm-1 (H bonded OH); may (MeOH) 247,257 and 287 nm; a (CD,OD), 3.10-4.05 (14H, m, CH2on (3) and 12 glucosylprotons, 4.75 [2H, m, 2 protons on (1)], 6.06 [H, dt, J 15.0 Hz, proton on C (4)], 6.53 [1 H, d, J 15 Hz, proton on C (5)], 6.65-6.90 (4H, m, Arom H), 7.07) 2H, d, Arom H).

trans-Rooperol 8,9,3',4' -tetraacetate (Id) Acetylation of trans-rooperol furnishes the amorphous tetra-acetate (Found: M+ 450, 13221 C25H22O8 requires: M+ 450.1 5536) (1 Hnmr, CDCI3): 82.28 (s, 1 2H, 4 x OAc), 3.33 (d, 2H, H-, J 5.0 Hz), 6.15 (dt, 1H, =CH-, J 15.0 and 5.0 Hz), 6.68 (d, 1 H, arom. -CH=, J 15.0 Hz), 7.00-7.50 (m, 6H aromatic).

trans-Rooperol 8,3'-di-P-D-glucopyranoside decaacetate Acetylation of (la) fumishes the crystalline deccacetate, m.p. 1340C (Found: C 57.37, H 5.39%..C49H54O24 requires: C 57.31, H 5.26%). ('Hnmr, CDCL3): ,S2.01, 2.04, 2.06 (s, 24H glucosyl acetates), 2.24 (s, 6H, 4', 9 OAc), 3.24 (d, 2H, H2-, J 5.0 Hz), 3.85, 4.1 7 (m, 6H, glucosyl, 5H, 6 CH2), 4.85-5.45 (m, 8H, glucosyl 1,2,3,4), 6.03 (dt, 1 H, =CH-, J 15.0 and 5.0 Hz), 6.53 (d, 1 H, arom-CH=, J 15.0 Hz), 6.75-7.35 (m, 6H aromatic).

trans-Rooperol 8,9,3',4'-tetramethyl ether.

Methylation of trans-rooperol (I) with diazomethane furnishes the tetramethyl ether as an oil (Found M+ 338.152247. C2,H2204 requires M+ 338.157680). (1Hnmr, CCl4): 33.24 (d, 2H, -CH2-,J 5.5 Hz), 3.75 (s, 1 2H, 4 x OMe), 5.96 (dt, 1 H, =CH-, J 15.0 and 5.5 Hz), 6.49 (d, 1 H, arom-CH=, J 15.0Hz), 6.49-7.00 (m, 6H, aromatic). (t3Cnmr, CCl4): 22.76 (t,CH2), 55.31, 55.39 (q, 4 x OMe), 82.65, 84.85 (s, IC-C-), 115.92, 130.04 (s, 1', 6 carbons), 109.56, 111.33, 111.61, 114.91, 119.13, 121.94, 124.42, 131.10 (d, 4.5, 7, 10, 1, 2', 5', 6 carbons), 148.84, 148.94, 149.32(s, 4 x aromatic C--O).

1 ,5-Bis-(3,4-dihydroxyphenyl)pentane.- Hydrogenation of trans-rooperol (I) with Adams' catalyst furnishes the hexahydro derivative, 1,5bis-(3,4-dihydroxyphenyl)pentane, m.p. 60 C (Found M+ 288 (34%) and m/e 123 (100%, 3,4dihydroxybenzyl carbocation) C17H2004 requires: M+ 288).

The compounds of the invention may be synthesized by the following scheme in which R', R2, R3 and R4 have the meanings described above:

ORI OR1 OR1 R2OC=-C1Ia+2-'C1I2-R2O CCH28r / + (PM7 P OR3 OR3 CH2Br + IPh)3 P R10-C,CHB"Rloj OR3 AC:CMg+8r+ (GL%1OR3 OR4 II 23Bromination 1. Oehydrobrominatinn Oecarboxytation COOlI + H C" H UIHX H (R1 =R3) H g 3 Hr HC"C;H UAIH 1OR3 (R2:R) (OR3 (OR3 OR OR4 OR Embodiments of the invention are described in the following Examples: EXAMPLE 1 Corms of hypoxis rooperi (2 kg) were grated into ethanol (2 I) and left at 250C for 48 hours. The ethanolic solution derived from this extract was collected by filtration. The solvent from the filtered extract was removed under vacuum to give a solid residue (180 g). This residue was first extracted in a soxhlet apparatus with hexane and subsequently with methanol (4 hours). Removal of the methanol afforded a brown powder (98 g).This material was separated on a silica gel column using the upper phase of a butanol:water:benzene:methanol (4:2:3:1 ) mixture as eluent.

Typical 1 g of crude extract yielded 550 mg of crystalline compound (la).

Hydrolysis of 1 a with p-glucosidase gave rooperol (1) and glucoside. The glucose was identified by paper co-chromatagraphy with authentic glucose. Rooperol (1) C17H14O4, M+ 282 did not give a satisfactory molecular ion in the mass spectrometer.

Hydrogenation with Pt/H2 in methanol however yielded a product which gave a satisfactory mass spectrum with M+ 288, indicating that 3 moles of hydrogen and been absorbed. The hydrogenated product is thus 1 ,5-bis-(3,4-dihydroxyphenyl) pentane.

EXAMPLE 2 The following further extractions were carried out for purposes of evaluation of the best methods and condition of extraction.

a) Grated corms (10keg) of Hypaxis rooperiwere air dried and the product (2.95 kg) was extracted for 1 hour with boiling water (20 I). Spray drying of this extract provided a partially water soluble light brown powder (550 g), which contained 20% trans-rooperol 8,3'-di-P-D-glucoside (la).

b) Gums obtained by centrifuging off the solid material from macerated corms (10 kg) of H. rooperi were diluted with cold water (1.5 I, 50C) and the centrifugate (4 1) was spray dried to yield a partially water soluble light cream coloured powder (900 g) which contained 30% of la.

c) Pulped corms of Hypoxis obtusa-nitida (10 kg) were extracted with cold water (15 I, 250C) with occasional stirring for 6 hours. The filtered extract (12.75 I) was freeze dried to yield a partially water soluble light brown powder (757 g) which contained 35% of 1 a(i). The residual wet pulp (10.8 kg) was extracted with boiling absolute ethanol (10.8 1) for 20 minutes. The filtered extract was concentrated under vacuum to remove most of the alcohol, diluted with water (1 litre), and then freeze dried to provide an almost completely water soluble light brown powder (361 g) which contained 43% of la (ii).

d) Pulped corms of H. obusa-nitida (10 kg) were extracted with boiling water (15 I) for 5 minutes.

The filtrate (10.4 I) was freeze dried to provide a partially water soluble light brown powder (742 g) which contained 37% of la.

e) Pulped corms of H. obusa-nitida (10 kg) were extracted with absolute ethanol (25 1, 250C) for 66 hours with continuous stirring. The filtrate (23 I) was concentrated under vacuum to remove most of the alcohol, diluted with water (1 litre) and then freeze dried to provide a water soluble dark brown powder (630 g) which contained 45% of la(i). The residual moist pulp (8.05 kg) was extracted with boiling absolute ethanol (20 I). The filtrate treated as described above was freeze dried to provide a dark brown almost completely water soluble powder (99 g) which contained 42% of la (ii).

f) Thinly sliced corms of H. obtusa-nitida (10 kg) were freeze dried to provide dried material (3.076 kg). This dried material was milled and a portion (300 g) was extracted with boiling 50% aqueous ethanol (5 I for 5 minutes. The filtrate was treated as described above and freeze dried to provide a light cream coloured water soluble powder 16 g) which contained 35% of la.

g) Pulped corms of young H. obtusa-nitida (1 kg) were extracted with boiling water (5 I) for 5 minutes. The filtrate on freeze drying provided a partially water soluble light brown powder (54 g) which contained 32% of la.

h) An extraction of young H. obtusa-nitida corms as described under (g) above, but prolonging the boiling process to 20 minutes, resulted in a relatively insolubie dark brown powder (82.3 g) which contained 27% of la.

i) Pulped corms of Spitoxene schlechlei on treatment with aqueous ethanol provided an extract which contained a substantial amount of la.

The above evaluations were obtained by comparative than layer chromatography and HPLC analysis.

STABILIZATION OF COMPOSITIONS CONTAINING ROOPEROL As mentioned above, rooperol and compositions containing rooperol are unstable in the presence of air or on prolonged standing, forming a dark coloured oxidation and/or polymerization product. This latter product itself has been shown to exhibit antibacterial and anticancer activity, but it is preferred to stabilize rooperol compositions by incorporating them in suitable buffers at pH about 5 to 7. A solution of rooperol in a phosphate buffer incorporating 10% acetic acid was found to be both bacteriostatic and bacteriocidal.

EXAMPLE 3 In order to demonstrate the antibacterial properties of the compounds of the invention, tests were carried out with both Gram-negative (Escherichia coll) and Gram-positive (Staphylococci aureus ROCHE) bacteria as test organism. The test material la was incorporated into a semi-solid nutrient which was chosen for its suitability as a growth medium for both organisms.

In some instances beta-glucosidase was added to the dissoived nutrient and pre-incubated at 37OC for 2 hours in order to produce the aglycon to the active agent.

This product was sterilised to destroy excess beta-glucosidase. The results are summarised in the following tables.

Table 1 Growth inhibition caused by Compound 1 a Test organism: Staphylococci aureus ROCHE Inhibition of growth over 24 and 48 hours

Dose 24 hours 48 hours mg/ml Active Control Active Control Remarks 1.0 mg ++++ ++++ ++++ ++++ No added p-glucosidase 2.0mg ++++ ++++ ++++ ++++ 4.0 mg +++(+) ++++ ++++ ++++ 0.050 mg +++ +++ ++++ ++++ Incubated with ss-glucosidase 0.125 mg # +++ +++ ++++ for 2 hours 0.250mg # +++ # ++++ 0.500 mg 1.000 mg Cb Table 2 Growth inhibition caused by compound la Test organism Eschirichia Colia

Inhibition of growth over 24 and 48 hours Dose mg/ml 24 hours 48 hours Media Active Control I Active Control I Remarks 5.0 +++ ++++ ++++ ++++(+) Without B glucosidase 0.25 ++(+) ++++ ++++ ++++(+) With addition of p-glucosidase 0.50 +(+) ++++ ++(+) 1.00 # ++++ #-+ ++++(+) 1 a was incubated with with ss-glucosidase 2.50 # ++++ # ++++(+) for 2 hours before adding to media In the case of E. coli and Staph. aureus, the effect of the hydrolysis with beta-glucosidase is obvious from the above tables.

The compound of the invention may be administered by any of the recognised routes such as orally, intraperitoneally or intravenously or may be incorporated into creams, lotions and ointments for topical application for example for the treatment of skin infections.

The dosages will vary depending on the mode of administration. For tablets, capsules and the like for oral administration the amount of active substance may be between 50 mg and 500 mg per unit dosage unit. It will be appreciated that inert additives such as sugars, tabletting aids such as stearates and the like and other commonly used agents, may be added. Rates of administration will vary substantially according to body mass, type of microorganism and other factors.

EXAMPLE 4 Toxicity tests were carried out on mice using groups of mice (equal number of males and females).

The weight of the animals ranged between 22 and 30 g. The follow-up observation period extended over 7 days following the administration of single doses.

The prepared solutions were filtered through Millex filter membranes (0.45 nm) before administered intravenously (I.V) in order to remove any particles which may complicate the interpretation of the results, and to obtain a sterile solution.

For oral (P.O) or intraperitoneal (I.P) route the solutions were administered as prepared, i.e.

without prior filtration.

The results are present in the following Tables Table 3

Cumulative % mortality rate due to Compound la Route Observation period in days Dose of mg/kg admin 1 2 1 3 5 7 2000 P.O. 0 0 0 0 0 1000 l.P. O 0 0 O O 2000 I.P. 20 40 40 40 40 500 l.V. 0 0 0 0 0 1000 I.V. 20 20 20 20 20 2000 I.V. 100 - - - - Table 4

Cumulative % mortality rate. Product of example Route Observation period in days Dose of mg/kg admin 1 2 3 5 7 1000 P.O. O 0 0 0 0 2000 P.O. 0 0 0 0 0 500 l.P. 0 0 0 0 0 1000 I.P. 10 20 20 20 20 2000 l.P. 60 75 80 80 80 500 I.V. O 0 0 0 0 1000 IV. 20 25 25 25 25 2000 I.V. 80 100 - - - EXAMPLE 5 In order to demonstrate the activities of the compounds of the invention, cytotoxicity tests were carried out on M(52)B cell culture system in vitro.

Mouse Sarkoma cells M(52)B were cultured as monolayers in M.E.M. with 10% foetal calf serum.

After confluency was achieved (usually within 34 days depending on the number of cells added per bottle) the cells were trypsinized. Once loose they were treated with M.E.M. containing 10% foetal calf serum in order to inactivate the trypsin.

An arbitrary volume of the suspension was then transferred to fresh nutrient solution rendering a final volume of 5 cm3.

The test material was added at different concentrations to either the freshly prepared cell suspension or to the 24 h developed cell culture in which the monolayer had a confluency of at least 40 to 50%.

All procedures were carried out under steriie conditions in a laminar flow chamber.

RESULTS The addition of adequate amounts of the test material resulted in cell death within 24 h. In other words the transferred cells failed to attach themselves on the bottom-surface of the tissue culture flask, while the non-treated control cells formed a confluent monolayer within 48-72 h.

It became apparent that there was some regeneration of the cells when smaller concentrations of test material were added for 24 h to the culture flask. However, it took more than 10 days to achieve a 4040% confluency, indicating that the larger proportion of the transferred cells were completely destroyed.

Table 1 Percentage confluency - compound la

Dose Observation in days Agent mg/ml 1 2 3 6 10 14 Control nil 60-70 90 90 split on - day 4 n/g n/g single a few #10 Compound 1 a 0.4 rn/g n/g rl/g ng single a few + 10 cells growth areas 0.8 n/g nig n/g n/g n/g n/g 1.6 9 n/g n/g n/g rMg n/e n/g 2A n/g n/g n/g rX n/g rX n/g = No growth, but some cells attached to bottom surface of tissue culture flask.

The compounds of the invention may be administered by any of the recognised routes such as orally, intraperitoneally or intravenously or may be incorporated into creams, lotions and ointments for topical application in the case of skin cancers.

The dosages will vary depending on the mode of administration. In tablets, capsules and the like for oral administration the amount of active substance may be between 50 mg and 500 mg per dosage unit and may be administered three times a day in 1 to 3 dosage units. Inert additives such as sugars, tabletting aid such as stearates and the like and other commonly used agents may be added.

EXAMPLE 6 Hypoxis extracts prepared as described in Example 2 were used to treat individual patients iwth various types of cancer with the following surprising results.

a) A 64 year old male patient who had suffered from skin cancer (face and arms) had developed an inoperable growth near his anus and had been operated for growths on his cheek and lips. After treatment had commenced with an extract prepared as described in Example 2a (200 mg doses three times per day) his condition improved in that all cancerous growth had started to regress within the first three weeks to finally disappear completely. The patient was treated six years ago and he is still alive and well.

b) The medical case history of a man now aged 79, reads as follows: At age 70 the patient had a laparotomy and colostomy.

Findings: a huge mass in the sigmoid colon, rectosigmoid junction and rectum. Due to very extensive periotoneal infiltration of the tumor and the fact that obstruction was present it was decided to biopsy several of the excrescences and to perform proximal colostomy. The pathology report recorded the presence of lymphosarcoma and this was later confirmed by an x-ray investigation.

Surgery was recommended to be followed by postsperative radiation treatment.

The surgeon on performing an exploratory laparotomy found a huge mass within the sigmoid colon and upper rectum. It had infiltrated onto the posterior abdominal and lateral pelvic walls making a hard unresectible mass.

After this operation the patient was not expected to live longer than two months. At this stage treatment commenced with a Hypoxis rooperi extract prepared as described in Example 2d with a daily dose of 3 times 200 mg. Four months later the patient was still alive and underwent surgery to free the colostomy from the abdominal wall and carry out a large bowel resection; no additional abnormalities were found in the rest of the peritoneal cavity. A pathology report on the excised 'intussuscepted' large bowel section recorded that the intussusception was oedematus and indo'rated (hardened) while the histology report records that sections of this bowel specimen showed congestion and superficial ulceration of the mucosa, but no evidence of lymphoma or malignancy.Since then the patient has continued to use Hypoxis extracts intermittently and he has regained his weight. He is now 79 years old and is active and healthy. There are no signs of a recurrence of the cancer.

c) An inoperable lung cancer was diagnosed in a middle aged female seven years ago. She commenced with a Hypoxis rooperi extract pepared as described in Example 2a with a dose of 600 mg per day. She received no chemotherapy or radiation treatment.

Within a month the patient reported a subjective improvement and within six months the patient had recovered completely. This patient is still alive, she takes the Hypoxis extract regularly and reports at least twice a year.

d) A bed-ridden male patient underwent radiation treatment for an inoperable lung cancer and he was not expected to survive for longer than two months. Treatment with Hypoxis extract prepared as described in Examples 2a and 2b using 600 mg per day resulted in an improvement enabling the patient to leave his bed and walk around. He was still alive six months later when, due to lack of communication, treatment with the extract was discontinued. Within two weeks the patient had to return to his bed. Treatment was resumed and within a week the patient was well enough to walk around again. Four months later this patient again discontinued treatment and he died shortly thereafter.

e) A 33 year old female patient after a radical mastectomy followed by radiation and chemotherapy developed metastatic cancer in the spine resulting in the destruction of one vertebra.

Further chemotherapy was refused by the patient who commenced treatment with a Hypoxis obtusanitida extract prepared as described in Example 2e(i) at a dose of 3 x 300 mg per day.

A month later a bone scan was performed, no sign of the cancer could be found and the patient was operated on within a week to rebuild the vertebra with a hipbone transplant. No sign of a residual cancer could be found during this operation.

f) Two females both suffering from severe skin cancer were treated with a Hypoxis rooperi extract prepared as described in Example 2a at a dose of 3 x 200 mg per day. Their condition cleared up within 60 days.

Claims (13)

1. A compound having the general formula:

in which the bonds between carbons 1 and 2 and carbons 4 and 5 may both be single, double or triple bonds, or one may be a single bond and the other a double or triple bond, or one may be a double bond of the other a triple bond and R1, R2 and R5 and R8 may, where apt, be hydrogen or other substituent groups; and R3 and R4 may be hydrogen or other substituent groups (such as halide, hydroxyl, amino, SH, amide or the like) or both taken together may be =O; or =S; and A and/B may be hydrogen or a substituent group and preferably a substituted or unsubstituted alkyl, aryl or heterocyclic group which may include one or more oxygen, nitrogen, sulphur or other atoms in the heteriocyclic structure.

2. A compound according to claim 1 in which A and/or B is the group.

in which R7 and R8 may be the same or different and may be hydrogen, alkyl, aryl, heterocyclic or acyl o other substituent groups including glycoside moieties; or A and/or B may constitute another aromatic system such as naphthyl, phenanthryl or the like with a free or protected hydroxy group in the meta and/or para position with respect of C-i' or a heterocyclic system which may include substituent groups.

3. A company according to claim 1 or claim 2 having the general formula:

in which A, B, R', R2, R3 and R4 have the same meaning as above.

4. A compound having the following general formula:

in which R2, R2, R3 and R4 may be the same or different and may be hydrogen, alkyl, aryl, heterocyclic, or acyl or other substituent groups including glycoside moieties, the benzene rings being optionally further functionalised with one or more substituent groups, and the hydrogen atoms in the aliphatic carbon chain being optionally replaced by one or more substituent groups; together with homologues, analogues and geometric isomers thereof; and, in particular the trans-isomer.

5. A compound according to claim 4 having the following meanings of R1, R2, R3 and R4 R1 R2 R3 R4 1 H H H H 1 a p-D-glucoside H ,B-D-glucoside H 1 b ss-D-glucoside H H H ic H H ,B-D-glucoside H 1 d CH3CO CH3CO CH3CO CH3CO 1 e H p-D-glucoside H p-D-glucoside if OMe OMe OMe OMe

6. Rooperol.

7. trans-rooperol 8,3'-,B-D-glucoside.

8. A derivative of the general formula of claim 4 selected from - the simple acyl derivatives such as the acetates of rooperol, i.e. trans-rooperol 8,9,3',4'tetraacetate (Id) the peracetates of la-Ic and of other di-, tri- and tetraglucosides, testers derived from other carboxylic acids such as propanoates along the homologues series to palmitates, oleates and the like, - sulphonates derived from p-toluene sulphonic acid and other sulphonic acids, -ethers derived from the phenolic of glucosidic (or glycosidic) hydroxy groups, especially the phenyl methyoxy- or ethoxy groups and the aromatic methylene dioxy group;; - acetals and acetonides and related functions in the carbohydrate moiety and hemiesters derived from dicarboxylic acids.

9. A method of synthesising a compound of the general formula in claim 4 by following one of the following schemes.

OR OR1 ORI R2 043C-CNa+CH2-CH2~R20t3- Cm CCH2CH2OHSR2OC:C(II2CII2C! OR3 OR3 r,Mi2Br / +1Ph)3 P RlO4C--CH EmRtOt-C-C Mg+8r H OR3 Ore OR3 rominaon OR3 H 1. Bromination r 2. Oehydrobromination,COOEt 3. Oecarboxylation \ \ COOH COOEt c,vH > I (R1=R3) mOH 'Hnp3 l H-C" 'H (R2:RA) H,C" e (R2,Rl, It OR4 n (%{{"HOR3 (Ĭ(OR3 ORt OR; OR;

10. A method of obtaining a compound according to any of the above claims 4 to 8 including the step of subjecting plant material of the family Hypoxidaceae to aqueous, alcoholic or aqueous alcoholic extraction and then recovering the compound from the extract.

11. A compound of the general formula in claim 4 prepared by a method according to claim 9 or claim 10.

12. A mono-, tri-ortetraglycoside of a compound according to claim 4 in which the glycoside moiety devices from arabinose, galactose, mannose, rhamnose, maltose and the like.

13. As an antimicrobial, particularly antibacterial or bacteriostatic agent, a compound according to any of claims 1 to 8, 11 or 12 or a pharmaceutical composition including such a compound.